Home > Products > Valid Products > AFD

000
FXUS63 KLBF 240434 AAB
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1134 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1134 PM CDT SAT MAY 23 2015

IFR/LIFR CIGS AND VSBY OVERNIGHT SHOULD IMPROVE TO VFR/MVFR SUNDAY
BY 18Z. ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY
WOULD LIKELY DEVELOP 20-24Z SUNDAY AFTN...MAINLY WEST OF HIGHWAY
83. THE NAM AND SREF SUGGEST ISOLATED SHOWER AND THUNDERSTORM
ACTIVITY IS POSSIBLE SUNDAY EVENING.

OVERNIGHT...A 700MB WARM FRONT LIFTS NORTH THROUGH THE FCST AREA.
WIDESPREAD CONVECTION ACROSS THE SOUTHERN PLAINS IS LIMITING STORM
COVERAGE ACROSS NEBRASKA. STILL...ISOLATED TSTM ACTIVITY
OVERNIGHT IS POSSIBLE...MAINLY WEST OF HIGHWAY 61...OTHERWISE
LIGHT RAIN...DRIZZLE AND SHOWERS PREVAIL.

&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...CDC
HYDROLOGY...MASEK







000
FXUS63 KLBF 240434 AAB
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1134 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1134 PM CDT SAT MAY 23 2015

IFR/LIFR CIGS AND VSBY OVERNIGHT SHOULD IMPROVE TO VFR/MVFR SUNDAY
BY 18Z. ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM ACTIVITY
WOULD LIKELY DEVELOP 20-24Z SUNDAY AFTN...MAINLY WEST OF HIGHWAY
83. THE NAM AND SREF SUGGEST ISOLATED SHOWER AND THUNDERSTORM
ACTIVITY IS POSSIBLE SUNDAY EVENING.

OVERNIGHT...A 700MB WARM FRONT LIFTS NORTH THROUGH THE FCST AREA.
WIDESPREAD CONVECTION ACROSS THE SOUTHERN PLAINS IS LIMITING STORM
COVERAGE ACROSS NEBRASKA. STILL...ISOLATED TSTM ACTIVITY
OVERNIGHT IS POSSIBLE...MAINLY WEST OF HIGHWAY 61...OTHERWISE
LIGHT RAIN...DRIZZLE AND SHOWERS PREVAIL.

&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...CDC
HYDROLOGY...MASEK








000
FXUS63 KLBF 232343 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
643 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 642 PM CDT SAT MAY 23 2015

IFR CIGS AND VSBY SHOULD BECOME WIDESPREAD OVERNIGHT AND THEN
IMPROVE TO VFR/MVFR SUNDAY BY 18Z. ISOLATED TO SCATTERED SHOWER
ACTIVITY WOULD LIKELY DEVELOP 20-24Z SUNDAY AFTN. TONIGHT...A
700MB WARM FRONT LIFTS NORTH THROUGH THE FCST AREA. TSTM ACTIVITY
ACROSS ERN COLO SHOULD PIVOT NORTHEAST INTO SWRN NEB AND WEAKEN
02Z-04Z. NUMEROUS SHOWERS AND ISOLATED TSTMS WOULD THEN LIFT
NORTH THROUGH NCNTL NEB 04Z-12Z.

&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...CDC
HYDROLOGY...MASEK







000
FXUS63 KLBF 232343 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
643 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 642 PM CDT SAT MAY 23 2015

IFR CIGS AND VSBY SHOULD BECOME WIDESPREAD OVERNIGHT AND THEN
IMPROVE TO VFR/MVFR SUNDAY BY 18Z. ISOLATED TO SCATTERED SHOWER
ACTIVITY WOULD LIKELY DEVELOP 20-24Z SUNDAY AFTN. TONIGHT...A
700MB WARM FRONT LIFTS NORTH THROUGH THE FCST AREA. TSTM ACTIVITY
ACROSS ERN COLO SHOULD PIVOT NORTHEAST INTO SWRN NEB AND WEAKEN
02Z-04Z. NUMEROUS SHOWERS AND ISOLATED TSTMS WOULD THEN LIFT
NORTH THROUGH NCNTL NEB 04Z-12Z.

&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...CDC
HYDROLOGY...MASEK








000
FXUS63 KLBF 232343 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
643 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 642 PM CDT SAT MAY 23 2015

IFR CIGS AND VSBY SHOULD BECOME WIDESPREAD OVERNIGHT AND THEN
IMPROVE TO VFR/MVFR SUNDAY BY 18Z. ISOLATED TO SCATTERED SHOWER
ACTIVITY WOULD LIKELY DEVELOP 20-24Z SUNDAY AFTN. TONIGHT...A
700MB WARM FRONT LIFTS NORTH THROUGH THE FCST AREA. TSTM ACTIVITY
ACROSS ERN COLO SHOULD PIVOT NORTHEAST INTO SWRN NEB AND WEAKEN
02Z-04Z. NUMEROUS SHOWERS AND ISOLATED TSTMS WOULD THEN LIFT
NORTH THROUGH NCNTL NEB 04Z-12Z.

&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...CDC
HYDROLOGY...MASEK








000
FXUS63 KLBF 232043
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
343 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.


&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...MASEK
HYDROLOGY...MASEK








000
FXUS63 KLBF 232043
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
343 PM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAY 23 2015

UPPER LEVEL CLOSED LOW ROTATING ACROSS THE FOUR CORNERS REGION THIS
AFTERNOON. SOUTHERLY/SOUTHEASTERLY MOIST WINDS HAVE HELD TEMPS DOWN
ACROSS THE AREA MOST OF THE DAY...WITH REPORTS GENERALLY IN THE 50S.
HOWEVER SOUTHWEST NEB STARTING TO SEE A LITTLE DRY AIR ALOFT WORK
INTO THE REGION AND EVEN SOME PEAKS OF SUN. SHOULD HELP TEMPS GET
INTO THE LOWER 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

COMPLEX WEATHER EXPECTED TONIGHT. FIRST OFF...WITH SOME CLEARING
ACROSS SW NEB AND THUNDERSTORMS FIRING OVER COLORADO...COULD SEE
SOME STRONG THUNDERSTORMS LIFT INTO THE REGION. PRIMARILY THINK THE
STORMS WILL REMAIN CLOSER TO THE LOW...TO THE WEST OF THE
CWA...HOWEVER A FEW STRAY STORMS MAY IMPACT SW NEB INTO THE SE
PANHANDLE. SECOND WILL BE THE CHANCE FOR SHOWERS AS A MID LEVEL WAVE
ROTATES AROUND THE MAIN LOW...AND ACROSS THE AREA. MARGINAL
ISENTROPIC LIFT AT THE 300K AND 305K SURFACE HOWEVER PRESS DEF 20MB
OR LESS. SHOULD GET SOME ISOLATED TO SCATTERED SHOWERS. LIFT INDEX
VALUES AROUND ZERO AND ONLY A COUPLE HUNDRED J/KG OF CAPE AT
BEST...SO MAINLY SHOWERS BUT COULD ALSO SEE A FEW WITH THUNDER.
FINALLY ACROSS THE NORTHERN HALF OF THE CWA LOW STRATUS WITH AREAS
OF FOG AND DRIZZLE WILL LIKELY PERSIST WITH THE EASTERLY UPSLOPE
FLOW WINDS CONTINUING. AS THE UPPER LEVEL SUPPORT BRINGS
SHOWERS...THE CIGS/FOG WILL LIFT...HOWEVER AS THE RAIN ENDS A RETURN
TO THE LOW CONDITIONS ARE LIKELY. TEMPS WITH SEE LITTLE MOVEMENT
OVERNIGHT AS MOST AREAS NEAR SATURATION ALREADY.

TOMORROW THE UPPER LOW WILL LIFT TO THE WESTERN HIGH PLAINS. MORNING
WILL CONTINUE TO SEE THE STRATUS/FOG/DRIZZLE/LIGHT SHOWERS AND MAYBE
A RUMBLE OF THUNDER HERE OR THERE. BY THE AFTERNOON A DRY SLOT WILL
WRAP INTO THE LOW AND THIN CLOUDS. THIS SHOULD HELP ALLOW TEMPS TO
WARM INTO THE 60S WITH AROUND 70 IN THE SOUTH AND FAR EAST. THIS
WILL ALSO BRING A LITTLE AFTERNOON SFC INSTABILITY. SPC CURRENTLY
HAS A MARGINAL RISK FOR SEVERE WEATHER. MODELS DEVELOP 1500 TO 2000
J/KG OF CAPE HOWEVER 0-6KM SHEAR IS 25 TO 30 KTS AND HELICITY OF
AROUND 100 M2/S2 OR LESS. HAIL LOOKS TO BE THE MAIN THREAT ALTHOUGH
IF A CLEARING POCKET DEVELOPS...TEMPS WOULD GET A QUICK BOOST UP AND
SEVERE THREAT WOULD INCREASE. WILL CONTINUE TO MONITOR.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAY 23 2015

STRONG INSTABILITY CONTINUES INTO THE EVENING BUT THE SHEAR IS WEAK
AND...WITH PRECIPITABLE WATER AT OR ABOVE 1.00 INCH...HEAVY RAIN
BECOMES THE PRIMARY THREAT SUNDAY NIGHT. ON MONDAY...COOLER DRIER
AIR COMES INTO WESTERN NEBRASKA AND THE CHANCES OF THUNDERSTORMS
SHIFT TO CENTRAL AND EASTERN NEBRASKA. HOWEVER...AS THE LOW MOVES
NORTHEASTWARD ACROSS WESTERN NEBRASKA...FRONTOGENESIS CONTINUES THE
PRECIPITATION INTO THE EVENING. THE GFS40 AND THE GEMNH SOLUTIONS
ARE SIMILAR...THOUGH THEY ARE A LITTLE SLOWER AS INDICATED BY THE
SLIGHTLY MORE NEGATIVE TILT TO THE UPPER TROUGH.

AFTER MONDAY NIGHT...THE MEDIUM RANGE MODELS DEVIATE SIGNIFICANTLY.
THE NAM12 SHOWS THE UPPER TROUGH PIVOTING ON THROUGH THE AREA AND
DRY WEATHER RESULTING. THE GEMNH IS SIMILAR TO THE NAM12 BUT THE
GFS40 HAS A SECOND TROUGH PIVOTING THROUGH TUESDAY AFTERNOON WITH
ENOUGH INSTABILITY FOR THUNDERSTORMS TO DEVELOP. SINCE TWO OF THE
THREE INDICATE DRY WEATHER...WE WILL SKEW THE FORECAST IN THAT
DIRECTION.

SOUTH FLOW ON THE HIGH PLAINS WILL HELP KEEP THE THETA-E RIDGE OVER
WESTERN NEBRASKA THROUGH THURSDAY NIGHT WHEN A FRONT FORCES IT
SOUTH. THE FRONT THEN STALLS ACROSS KANSAS. IN THE MEANTIME...THE
PRESENCE OF A SURFACE BOUNDARY IN THE THETA-E GRADIENT WILL BRING
CHANCES OF THUNDERSTORMS WEDNESDAY AFTERNOON AND EVENING AND AGAIN
THURSDAY AFTERNOON AND EVENING. FOR WEDNESDAY EVENING...THE
SURFACE-BASED CONVECTIVE POTENTIAL ENERGY INCREASES TO MORE THAN
2000J/KG WITH 0-6KM BULK SHEAR OF 20-30KT WHICH DOES ALLOW POTENTIAL
FOR LARGE HAIL. FRIDAY LOOKS TO BE MORE FAVORABLE FOR SEVERE WEATHER
IN CENTRAL AND NORTH CENTRAL NEBRASKA WITH SURFACE-BASED CONVECTIVE
POTENTIAL ENERGY OF 3000-4000J/KG AND 0-6KM BULK SHEAR OF 25-35KT.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.


&&

.HYDROLOGY...
ISSUED AT 340 PM CDT SAT MAY 23 2015

THE SOUTH PLATTE RIVER IS HOLDING STEADY OR SLIGHTLY FALLING...AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF DAYS. STILL AMPLE
SNOW MELT WHICH WILL CONTINUE TO RESULT IN ELEVATED FLOWS INTO JUNE.
ALSO GOING TO ADD SOME WATER AS THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL MOVE ACROSS NORTHEAST COLORADO AND THE SOUTHWESTERN
NEBRASKA PANHANDLE TONIGHT. THIS WILL BE MONITORED CLOSELY AS THIS
AREA IS BECOMING MORE SATURATED AND COULD SEE MORE RUNOFF...WHICH
ENDS UP IN THE SOUTH PLATTE RIVER. AT THIS TIME A SECOND RISE IS
ANTICIPATED TO MOVE DOWN THE RIVER FROM MID WEEK THROUGH THE
WEEKEND. THIS CREST IS EXPECTED TO BE BELOW THE FIRST
CREST...HOWEVER WITH RAIN CHANCES OVER THE NEXT COUPLE OF DAYS AND
AGAIN DURING THE WEEK...THE SECOND CREST HEIGHT IS NOT A CERTAINTY.
ANYONE ALONG THE SOUTH PLATTE RIVER WILL NEED TO CONTINUE TO MONITOR
THE LATEST FORECAST.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...SPRINGER
AVIATION...MASEK
HYDROLOGY...MASEK







000
FXUS63 KLBF 231821
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
121 PM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...MASEK







000
FXUS63 KLBF 231821
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
121 PM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...MASEK






000
FXUS63 KLBF 231821
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
121 PM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...MASEK






000
FXUS63 KLBF 231821
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
121 PM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 120 PM CDT SAT MAY 23 2015

STORM SYSTEM CONTINUES TO SLOWLY MOVE ACROSS THE AREA. LOW CLOUDS
AND AREAS OF LOW VISIBILITIES FROM FOG WILL BE COMMON OVER THE
NEXT 24 HOURS. SOME SCATTERED SHOWERS WILL LIKELY LIFT ACROSS THE
AREA THIS EVENING AND OVERNIGHT...AND COULD BRIEFLY RAISE CIGS
AND VISBY...HOWEVER WHEN NOT IN SHOWERS EXPECT LOW IFR CONDITIONS.
SOME ISOLATED TO SCATTERED THUNDERSTORMS ARE ALSO POSSIBLE THIS
EVENING AND WILL MAINLY IMPACT SOUTHWEST NEBRASKA.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...MASEK







000
FXUS63 KLBF 230834
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
334 AM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...KECK








000
FXUS63 KLBF 230834
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
334 AM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...KECK









000
FXUS63 KLBF 230834
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
334 AM CDT SAT MAY 23 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT SAT MAY 23 2015

TEMPERATURES FORECAST CHALLENGE TODAY AS SLOW MOVING UPPER LOW
CENTER NEAR THE FOUR CORNERS REGION AND STEADY FLOW OF MOISTURE
NORTH TO KEEP CONSIDERABLE CLOUD COVERAGE OVERHEAD. MODELS IN FAIR
AGREEMENT HOWEVER CREATE A SPREAD IN TEMPERATURES. FORECAST TRENDED
TOWARD A MODEL BLEND AND TOWARD COOLER GUIDANCE VALUES.

THE UPPER LOW NEAR WEST CENTRAL COLORADO WILL BE SLOW TO LIFT OUT
YET CONTINUE TO EJECT DISTURBANCES NORTHEAST ACROSS THE AREA TODAY.
THIS MORNING A FEW SHOWERS...MORE PREVALENT ACROSS SOUTHWEST
NEBRASKA WILL LIFT NORTHEAST TO PRODUCE RAINFALL AMOUNTS NEAR A
QUARTER INCH AS A FEW THUNDERSTORMS LIFT NORTHEAST THROUGH THE FAR
SOUTHWEST. FURTHER NORTH THE DEEP MOISTURE...LIGHT SOUTHEAST WINDS
AND CLOSE TEMP AND DEW POINT VALUES SEEN ACROSS THE AREA WILL KEEP
AREAS OF FOG AND LIGHT DRIZZLE GOING THROUGH NOONTIME. THIS
AFTERNOON GREATER INSTABILITY WILL EXTEND NORTH...WHERE A SLIGHT
CHANCE FOR SEVERE THUNDERSTORMS EXISTS IN THE SOUTHWEST THIS
AFTERNOON. THEN GENERAL THUNDERSTORMS POSSIBLE SOUTH OF A LINE FROM
NEAR ELLSWORTH...BRADY AND EUSTIS. HIGH TEMPERATURES WILL RANGE FROM
THE UPPER 50S IN THE NORTHERN SANDHILLS TO THE MID 60S SOUTH AND
NORTH CENTRAL.

TONIGHT LITTLE CHANGE AS A WARM FRONT LIFTS NORTH TO THE NEB. AND
KANSAS STATE LINE BY MORNING. CONSIDERABLE CLOUDINESS WILL LINGER
THAT WILL HELP KEEP TEMPERATURES UP WITH LOWS DROPPING TO AROUND 50
WEST TO MIDDLE 50S NORTH CENTRAL. AS DISTURBANCES LIFT NORTH
OVERNIGHT THE CHANCE FOR SHOWERS AND THUNDERSTORMS REMAIN.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT MAY 23 2015

THE LONG TERM PERIOD BEGINS WITH A LARGE UPPER LEVEL LOW PUSHING
EAST INTO THE CENTRAL CONUS. MODELS ARE COMING INTO BETTER AGREEMENT
WITH THEIR HANDLING OVER MOISTURE ADVECTION PATTERNS AND TIMING OF
SUBTLE UPPER LEVEL FEATURES FOR SUNDAY. AS THE UPPER LEVEL LOW MOVES
INTO THE DAKOTAS DRIER AIR PUSHES NORTHEAST AND THROUGH WESTERN AND
CENTRAL NEBRASKA. HAVE LOWERED POPS FOR MOST OF THE CWA
SUNDAY...WITH THE EXCEPTION OF FAR NORTHWEST NEBRASKA WHERE A SLOW
MOVING PACIFIC FRONT SHOULD SERVE AS FOCUS FOR SHOWERS AND
THUNDERSTORMS. THE FRONT ADVANCES EASTWARD LATE IN THE DAY AND
OVERNIGHT WITH UPPER LEVEL SUPPORT BY THE WAY OF A WEAK PV MAX
ROUNDING THE BASE OF THE MAIN UPPER LEVEL LOW. PRECIPITATION
COVERAGE WILL INCREASE IN THE VICINITY OF THE FRONT...ESPECIALLY AS
THE LLJ CRANKS UP BY LATE EVENING. A FEW STRONG TO SEVERE STORMS
WILL BE POSSIBLE IN THE WESTERN SANDHILLS DURING THE EVENING
HOURS...BUT THE TIME WINDOW IS NARROW AS INSTABILITY WANES AFTER
SUNSET.

FORECAST DRIES OUT FOR MOST OF THE AREA BY LATE MONDAY AS THE FRONT
PUSHES EAST AND SFC HIGH PRESSURE BUILDS IN FROM THE WEST.
SUBSIDENCE ALOFT IN THE WAKE OF THE DEPARTING UPPER LEVEL LOW
SHOULD HELP SCOUR OUT MOST OF THE RESIDUAL CLOUD COVER. MONDAY
NIGHT LOOKS COOL WITH MOSTLY CLEAR SKIES AND WEAK NORTHWEST
DRAINAGE WINDS. HOWEVER WITH DEWPOINTS STILL IN THE 40S NOT
ANTICIPATING FROST TO BE AN ISSUE.

SUNSHINE AND NEAR NORMAL TEMPERATURES EXPECTED FOR TUESDAY IN THE
PRESENCE OF SHORTWAVE RIDGING ALOFT. A FEW DIURNALLY DRIVEN SHOWERS
AND STORMS WILL BE POSSIBLE ACROSS PARTS OF NORTH CENTRAL NEBRASKA
AS A WEAK PERTURBATION IN THE MEAN UPPER LEVEL FLOW ARRIVES LATE
IN THE DAY...HOWEVER FORCING LOOKS MEAGER AT BEST SO COVERAGE
SHOULD BE ISOLATED. ANOTHER DEEP TROUGH BEGINS TO DIG INTO THE
WESTERN CONUS BY WEDNESDAY. LATEST RUNS OF THE GFS AND EURO
ADVERTISE DECENT MOISTURE ADVECTION FROM THE GULF OF MEXICO AND
ALOFT OFF THE EASTERN PACIFIC...WHICH WILL SET THE STAGE FOR MORE
RAINFALL OVER THE CENTRAL PLAINS TOWARD THE LATTER HALF OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM...KECK
LONG TERM...MARTIN
AVIATION...KECK








000
FXUS63 KLBF 230536
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1236 AM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...KECK
HYDROLOGY...MASEK









000
FXUS63 KLBF 230536
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1236 AM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...KECK
HYDROLOGY...MASEK










000
FXUS63 KLBF 230536
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1236 AM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...KECK
HYDROLOGY...MASEK










000
FXUS63 KLBF 230536
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1236 AM CDT SAT MAY 23 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAY 23 2015

IFR/LIFR CONDITIONS EXPECTED AT TERMINALS KLBF AND KVTN THROUGH
12Z. LOW CLOUDS WITH IFR CEILINGS AND VISIBILITIES WILL CONTINUE
OVER WESTERN NEBRASKA THROUGH THE EARLY MORNING HOURS. SOUTHEAST
WINDS AT 5 TO 15 MPH WILL KEEP A STEADY STREAM OF MOISTURE IN THE
UPSLOPE FLOW FOR LITTLE CHANGE THROUGH THE DAY SATURDAY. THERE IS THE LOW
CHANCE OF AN AN ISOLATED THUNDERSTORM OVER SOUTHWEST NEBRASKA
BETWEEN KIML AND KLBF. HOWEVER LATEST MODEL DATA KEEPS BETTER
INSTABILITY TO THE SOUTHWEST WITH STORMS OVER FAR NORTHWEST KANSAS
TO WEAKEN WHILE MOVING NORTHEAST...WHILE THE CHANCE FOR DRIZZLE
AND FOG LINGERS OVERNIGHT.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...KECK
HYDROLOGY...MASEK









000
FXUS63 KLBF 222353 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
653 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 752 PM CDT FRI MAY 22 2015

WIDESPREAD LIGHT RAIN WILL CONTINUE OVER WESTERN NEBRASKA TONIGHT
WITH THUNDERSTORMS OVER SOUTHWEST NEBRASKA AFTER MIDNIGHT. MVFR
CEILINGS WILL GIVE WAY TO IFR CEILINGS THROUGH THE EVENING AND
CONTINUE INTO SATURDAY MORNING WITH SOME MVFR VISIBILITIES IN
STRATUS AND FOG.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MASEK







000
FXUS63 KLBF 222353 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
653 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 752 PM CDT FRI MAY 22 2015

WIDESPREAD LIGHT RAIN WILL CONTINUE OVER WESTERN NEBRASKA TONIGHT
WITH THUNDERSTORMS OVER SOUTHWEST NEBRASKA AFTER MIDNIGHT. MVFR
CEILINGS WILL GIVE WAY TO IFR CEILINGS THROUGH THE EVENING AND
CONTINUE INTO SATURDAY MORNING WITH SOME MVFR VISIBILITIES IN
STRATUS AND FOG.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MASEK








000
FXUS63 KLBF 222051
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
351 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI MAY 22 2015

A BAND OF LIGHT TO MODERATE RAINFALL WILL LIFT ACROSS THE AREA
THIS AFTERNOON. MORE LIGHT RAIN SHOWERS WILL FILL IN BEHIND THE
BAND. MVFR TO LOCALLY IFR CONDITIONS WILL ACCOMPANY THE RAIN.
OVERNIGHT A CHANCE FOR A FEW THUNDERSTORMS COULD LIFT INTO SW NEB.
OTHERWISE MVFR/IFR OR LOWER CIGS/FOG DEVELOPS ACROSS THE AREA.
THIS WILL BE SLOW TO IMPROVE IN THE MORNING.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...MASEK
HYDROLOGY...MASEK







000
FXUS63 KLBF 222051
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
351 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 350 PM CDT FRI MAY 22 2015

LOW PRESSURE SYSTEM  DIGGING ACROSS THE DESERT SOUTHWEST. WEAK
RIDGING ACROSS THE MISS RVR VALLEY. UPPER LEVEL DISTURBANCE ROTATING
ACROSS THE HIGH PLAINS. SEVERAL BANDS OF LIGHT TO MODERATE RAIN
LIFTING ACROSS THE STATE. CLOUDS AND RAIN KEEPING TEMPS COOL FOR THE
LATTER PART OF MAY...WITH MOST SITES IN THE UPPER 40S TO LOWER
50S...EXCEPT FOR FAR NORTHERN NEB...WHERE THE RAIN IS JUST MOVING
INTO. THERE SOME SUN ALLOWED TEMPS TO WARM CLOSE TO 60.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

UPPER LEVEL LOW WILL CONTINUE TO ROTATE ACROSS THE AREA AND IMPACT
THE REGION TONIGHT. THE BAND OF RAIN...LIGHT TO MODERATE...WILL
CONTINUE TO LIFT NORTH ACROSS THE AREA OVERNIGHT. MEANWHILE A POCKET
OF CLEARING AND A WEAK CAP HAS ALLOWED SOME INSTABILITY TO DEVELOP
ACROSS NORTHEAST COLORADO. A FEW STORMS HAVE BEGUN TO FIRE AND WILL
NEED TO MONITOR THIS AS IT LIFTS ACROSS THE AREA OVERNIGHT. MODELS
IN AGREEMENT TAKING THE STORMS AND CONTINUING THE ACTIVITY AS IT
MOVES IN THE SW FLOW. THE STORMS WILL HAVE TO BECOME ELEVATED TO
SURVIVE AND MODELS KEEP SOME NEG LIFTED INDEX VALUES AND SOME WEAK
MUCAPE. SHOULD BE ENOUGH TO KEEP SHOWERS AND THUNDERSTORMS GOING.
NOT LOOKING AT SEVERE AS ROTATION IS WEAK...BUT CANNOT RULE OUT THE
LIGHTNING STRIKES.

MEANWHILE THE BOUNDARY LAYER IS SATURATED AND NEAR TERM MODELS ARE
FAVORING FOG AND DRIZZLE. THUS A COMPLEX FORECAST OVERNIGHT AS THE
ELEVATED SHOWERS/THUNDER LIFT ACROSS THE AREA ON TOP OF THE
FOG/DRIZZLE. TYPICALLY AS THE SHOWERS MOVE ACROSS THE AREA...THE FOG
MAY LIFT SOME. AS FOR TEMPS...THE CLOUDS AND HIGH DEW PTS WILL LIMIT
COOLING AND LOWS IN THE MID TO UPPER 40S.

TOMORROW THE DESERT SOUTHWEST LOW WILL LIFT TO THE 4 CORNERS BY MID
DAY. SOUTHERLY FLOW AHEAD OF THE LOW WILL CONTINUE TO FEED SOME WEAK
INSTABILITY AND WILL NEED A CHANCE FOR STORMS. SOME WARMER AIR WILL
ADVECT NORTHWARD...ALTHOUGH CLOUDS WILL LIMIT WARMING. HAVE GONE
WITH THE COOLER SIDE OF GUIDANCE...WHICH IS CLOSER TO THE MAV
GUIDANCE. IF THERE ARE A FEW BREAKS IN THE CLOUDS IN THE
AFTERNOON...TEMPS COULD SEE A BRIEF BUMP OF 5 TO 10 DEGREES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 350 PM CDT FRI MAY 22 2015

SATURDAY NIGHT THROUGH MONDAY...THE UPPER LOW LIFTS INTO THE DAKOTAS
BY MONDAY. THE MODELS SUGGEST A PRONOUNCED H700MB WARM FRONT WILL
LIFT THROUGH THE FCST AREA SATURDAY NIGHT. THERE IS GOOD AGREEMENT
FOR DEFINITE TSTM COVERAGE ALONG AND WEST OF HIGHWAY 61 WITH
CHANCE/LIKELY COVERAGE EAST OF 61. THE FORECAST STRATEGY IN TERMS OF
POPS AND QPF FOLLOWS A BLEND OF THE NAM...GEM...GFS...ARW AND NMM.

RAIN CHANCES DECREASE SOMEWHAT AFTER SATURDAY NIGHT BUT A SECOND
WEAKER LOBE OF H700MB FORCING LIFTS THROUGH SUNDAY NIGHT BEFORE THE
ENTIRE UPPER LEVEL LOW MIGRATES INTO THE DAKOTAS MONDAY. LIKELY POPS
ARE IN PLACE SUNDAY EVENING. OTHERWISE POPS ARE CHANCE OR SLIGHT
CHANCE GIVEN THE WEAK FORCING. COLD AIR ALOFT MONDAY MIGHT BE
SUFFICIENT FOR DIURNALLY DRIVEN CONVECTION. K INDICES SATURDAY NIGHT
THROUGH MONDAY ARE WELL INTO THE 30S SUPPORTING TSTM DEVELOPMENT.

TOTAL QPF SATURDAY NIGHT THROUGH MONDAY WOULD BE 1/3 TO 1 INCH WITH
HIGHEST AMOUNTS WEST OF HIGHWAY 61 ACROSS THE PANHANDLE WITH LOWEST
AMOUNTS SOUTH AND EAST. LOCALLY HIGHER AMOUNTS COULD TOTAL 2
INCHES...MAINLY ACROSS THE PANHANDLE.

SPC SUGGESTS SEVERE STORM DEVELOPMENT ACROSS SOUTHWEST NEB SATURDAY
AFTN AND EVENING. THESE STORMS WOULD LIKELY LIFT NORTH AND WEAKEN. A
WARM FRONT SHOULD REMAIN SOUTH OF THE FCST AREA NEAR DURING THE DAY
AND LIFT THROUGH THE FCST AREA SATURDAY NIGHT. SOME SOLNS KEEP THE
LOW OVER NORTHEAST COLO UNTIL SUNDAY NIGHT. EITHER WAY...A PACIFIC
FRONT SHOULD SWEEP INTO WRN NEB SUNDAY AFTN TRIGGERING MORE RAIN FOR
SUNDAY NIGHT.

THE TEMPERATURE FORECAST IS BLENDED MODEL DATA FOR HIGHS IN THE 60S
AND 70S SUNDAY AND MONDAY. THE NAM WAS THE WARMEST MODEL WITH HIGHS
NEAR 80 SUNDAY. PARTIAL CLEARING SHOULD DEVELOP SUNDAY AND BECOME
MORE WIDESPREAD MONDAY. DEPENDING ON THE AMOUNT OF CLEARING SUNDAY
AND TIME BEFORE DESTABILIZATION OCCURS COULD HAVE A BIG IMPACT ON
HIGHS.

MONDAY NIGHT THROUGH FRIDAY...THERE IS REASONABLE AGREEMENT IN THE
MODELS THAT ANOTHER DEEP TROF OR UPPER LOW WILL MIGRATE THROUGH THE
ROCKIES PRODUCING TSTMS THURSDAY AND FRIDAY...POSSIBLY AS EARLY AS
WEDNESDAY. THE GEF ACTUALLY INDICATES A LIKELY CHANCE THURSDAY AND
FRIDAY. THE UPPER LEVEL DISTURBANCE WILL BE OPERATING ON A COLD
FRONT FROM A LATE SEASON BATCH OF HIGH PRESSURE FROM THE ARCTIC.

THE GFS SHOWS PWAT WELL OVER 1 INCH EAST OF HIGHWAY 83 AS THE FRONT
DROPS INTO WRN NEB. K INDICES IN THE ECM AND GFS RISE TO 35C TO 45C
SUPPORTING HEAVY TSTMS. THE FORECAST HOLD POPS AT THE CHANCE
CATEGORY PENDING CONTINUITY IN THE MODELS.

TEMPERATURES COULD ACTUALLY REACH 80F WEDNESDAY IN A FEW AREAS. A
MOISTURE LADEN WARM RETURN FLOW SETS UP TUESDAY NIGHT. THE COLD
FRONT ARRIVES FRIDAY SUGGESTING THURSDAY COULD BE MILD ALSO.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI MAY 22 2015

A BAND OF LIGHT TO MODERATE RAINFALL WILL LIFT ACROSS THE AREA
THIS AFTERNOON. MORE LIGHT RAIN SHOWERS WILL FILL IN BEHIND THE
BAND. MVFR TO LOCALLY IFR CONDITIONS WILL ACCOMPANY THE RAIN.
OVERNIGHT A CHANCE FOR A FEW THUNDERSTORMS COULD LIFT INTO SW NEB.
OTHERWISE MVFR/IFR OR LOWER CIGS/FOG DEVELOPS ACROSS THE AREA.
THIS WILL BE SLOW TO IMPROVE IN THE MORNING.

&&

.HYDROLOGY...
ISSUED AT 350 PM CDT FRI MAY 22 2015

RAINFALL TODAY SHOULD HAVE MINIMAL IMPACT ON THE RIVER AS THE RAIN
HAS BEEN STEADY BUT LIGHT. THE GROUND SHOULD BE ABLE TO ABSORB MOST
OF IT. HOWEVER STILL SEEING ANOTHER PULSE MOVING DOWN THE SOUTH
PLATTE RIVER AND WHILE THE RIVER IS CURRENTLY HOLDING STEADY TO
LOWERING...ANOTHER RISE IS EXPECTED NEXT WEEK. THERE REMAINS AN
HIGHER THAN NORMAL SNOW PACK IN THE MOUNTAINS WHICH WILL COMBINE
WITH SOME CONVECTION POSSIBLE OVER THE WEEKEND AND AGAIN NEXT WEEK
IN COLORADO WHICH WILL LIKELY PROLONG THE ELEVATED FLOW INTO JUNE.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...CDC
AVIATION...MASEK
HYDROLOGY...MASEK








000
FXUS63 KLBF 221754
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1254 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI MAY 22 2015

A BAND OF LIGHT TO MODERATE RAINFALL WILL LIFT ACROSS THE AREA
THIS AFTERNOON. MORE LIGHT RAIN SHOWERS WILL FILL IN BEHIND THE
BAND. MVFR TO LOCALLY IFR CONDITIONS WILL ACCOMPANY THE RAIN.
OVERNIGHT A CHANCE FOR A FEW THUNDERSTORMS COULD LIFT INTO SW NEB.
OTHERWISE MVFR/IFR OR LOWER CIGS/FOG DEVELOPS ACROSS THE AREA.
THIS WILL BE SLOW TO IMPROVE IN THE MORNING.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MASEK
HYDROLOGY...CLB





000
FXUS63 KLBF 221754
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1254 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI MAY 22 2015

A BAND OF LIGHT TO MODERATE RAINFALL WILL LIFT ACROSS THE AREA
THIS AFTERNOON. MORE LIGHT RAIN SHOWERS WILL FILL IN BEHIND THE
BAND. MVFR TO LOCALLY IFR CONDITIONS WILL ACCOMPANY THE RAIN.
OVERNIGHT A CHANCE FOR A FEW THUNDERSTORMS COULD LIFT INTO SW NEB.
OTHERWISE MVFR/IFR OR LOWER CIGS/FOG DEVELOPS ACROSS THE AREA.
THIS WILL BE SLOW TO IMPROVE IN THE MORNING.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MASEK
HYDROLOGY...CLB






000
FXUS63 KLBF 221754
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1254 PM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1252 PM CDT FRI MAY 22 2015

A BAND OF LIGHT TO MODERATE RAINFALL WILL LIFT ACROSS THE AREA
THIS AFTERNOON. MORE LIGHT RAIN SHOWERS WILL FILL IN BEHIND THE
BAND. MVFR TO LOCALLY IFR CONDITIONS WILL ACCOMPANY THE RAIN.
OVERNIGHT A CHANCE FOR A FEW THUNDERSTORMS COULD LIFT INTO SW NEB.
OTHERWISE MVFR/IFR OR LOWER CIGS/FOG DEVELOPS ACROSS THE AREA.
THIS WILL BE SLOW TO IMPROVE IN THE MORNING.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MASEK
HYDROLOGY...CLB





000
FXUS63 KLBF 221148
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
648 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 648 AM CDT FRI MAY 22 2015

FOR THE KLBF TERMINAL...LIGHT RAIN WILL MOVE INTO THE TERMINAL
AROUND 14Z THIS MORNING WITH CIGS FALLING TO BELOW 1000 FT AGL.
LOW CIGS AND LIGHT RAIN WILL CONTINUE INTO MID AFTERNOON. RAIN
WILL END TEMPORARILY BY 22Z WITH CIGS INCREASING TO 1500 FT AGL.
CIGS WILL FALL TO UNDER 1000 FT AGL LATER THIS EVENING WITH AN
INCREASED THREAT FOR THUNDERSTORMS AFTER 04Z SATURDAY. FOR THE
KVTN TERMINAL...EXPECT OVERCAST SKIES WITH CIGS AROUND 10000 FT
AGL...FALLING TO AROUND 2500 FT AGL THIS AFTERNOON. LIGHT RAIN
WILL COMMENCE BY 21Z WITH CIGS FALLING DOWN TO 700 FT AGL. CIGS
WILL FALL TO UNDER 500 FT AGL OVERNIGHT WITH PATCHY FOG DEVELOPING
AFTER 06Z SATURDAY. VISBYS MAY DROP AS LOW AS 2SM.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB







000
FXUS63 KLBF 221148
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
648 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 648 AM CDT FRI MAY 22 2015

FOR THE KLBF TERMINAL...LIGHT RAIN WILL MOVE INTO THE TERMINAL
AROUND 14Z THIS MORNING WITH CIGS FALLING TO BELOW 1000 FT AGL.
LOW CIGS AND LIGHT RAIN WILL CONTINUE INTO MID AFTERNOON. RAIN
WILL END TEMPORARILY BY 22Z WITH CIGS INCREASING TO 1500 FT AGL.
CIGS WILL FALL TO UNDER 1000 FT AGL LATER THIS EVENING WITH AN
INCREASED THREAT FOR THUNDERSTORMS AFTER 04Z SATURDAY. FOR THE
KVTN TERMINAL...EXPECT OVERCAST SKIES WITH CIGS AROUND 10000 FT
AGL...FALLING TO AROUND 2500 FT AGL THIS AFTERNOON. LIGHT RAIN
WILL COMMENCE BY 21Z WITH CIGS FALLING DOWN TO 700 FT AGL. CIGS
WILL FALL TO UNDER 500 FT AGL OVERNIGHT WITH PATCHY FOG DEVELOPING
AFTER 06Z SATURDAY. VISBYS MAY DROP AS LOW AS 2SM.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB








000
FXUS63 KLBF 221148
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
648 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 648 AM CDT FRI MAY 22 2015

FOR THE KLBF TERMINAL...LIGHT RAIN WILL MOVE INTO THE TERMINAL
AROUND 14Z THIS MORNING WITH CIGS FALLING TO BELOW 1000 FT AGL.
LOW CIGS AND LIGHT RAIN WILL CONTINUE INTO MID AFTERNOON. RAIN
WILL END TEMPORARILY BY 22Z WITH CIGS INCREASING TO 1500 FT AGL.
CIGS WILL FALL TO UNDER 1000 FT AGL LATER THIS EVENING WITH AN
INCREASED THREAT FOR THUNDERSTORMS AFTER 04Z SATURDAY. FOR THE
KVTN TERMINAL...EXPECT OVERCAST SKIES WITH CIGS AROUND 10000 FT
AGL...FALLING TO AROUND 2500 FT AGL THIS AFTERNOON. LIGHT RAIN
WILL COMMENCE BY 21Z WITH CIGS FALLING DOWN TO 700 FT AGL. CIGS
WILL FALL TO UNDER 500 FT AGL OVERNIGHT WITH PATCHY FOG DEVELOPING
AFTER 06Z SATURDAY. VISBYS MAY DROP AS LOW AS 2SM.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB








000
FXUS63 KLBF 220901
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
401 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...POWER
HYDROLOGY...CLB







000
FXUS63 KLBF 220901
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
401 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...POWER
HYDROLOGY...CLB







000
FXUS63 KLBF 220901
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
401 AM CDT FRI MAY 22 2015

.SYNOPSIS...
ISSUED AT 345 AM CDT FRI MAY 22 2015

H5 ANALYSIS FROM THIS EVENING HAD CLOSED LOW PRESSURE
OFF THE CENTRAL CA COAST...WHILE A LOW AMPLITUDE RIDGE EXTENDED FROM
TEXAS NWD INTO THE NEBR PANHANDLE. FURTHER EAST...STRONG LOW
PRESSURE WAS NOTED OVER FAR SRN PORTIONS OF HUDSON BAY WITH A TROUGH
EXTENDING SWD INTO THE OHIO VALLEY. WV IMAGERY TONIGHT HAS THE
CALIFORNIA LOW NOW APPROACHING THE SRN COAST OF CALIFORNIA. A LEAD
SHORTWAVE WAS PUSHING INTO SERN COLORADO ATTM. THIS FEATURE HAS
FIRED OFF SHOWERS ACROSS EASTERN COLORADO AND WESTERN KANSAS
OVERNIGHT. AS OF 230 AM CDT...THE LEADING EDGE OF THESE SHOWERS WERE
LOCATED ROUGHLY 30 MILES SOUTH OF A GOODLAND...TO COLBY TO HILL CITY
KANSAS LINE. TRACKING THE PROGRESSION OF THESE SHOWERS...THEY SHOULD
BEGIN TO APPROACH FAR SOUTHERN PORTIONS OF THE FORECAST AREA SOME
TIME AROUND 6 AM CDT. AT THE SURFACE...HIGH PRESSURE WAS PRESENT
OVER EASTERN NEBRASKA AND EASTERN KS. THIS HAS ALLOWED SRLY AND
SERLY WINDS TO DEVELOP ACROSS THE WESTERN HALF OF THE FORECAST AREA
TONIGHT...INCREASING DEW POINTS INTO THE LOWER TO MID 40S. COMPARED
TO LAST NIGHT...TEMPERATURES WERE MUCH WARMER DUE TO THE COMBINATION
OF CLOUDS AND INCREASED LOW LEVEL MOISTURE. READINGS AS OF 3 AM CDT
RANGED FROM 42 AT AINSWORTH TO 51 AT OGALLALA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE MAIN FORECAST CHALLENGE IS
PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. PRECIPITATION WILL
COME IN TWO WAVES OVER THE NEXT 24 HOURS. THE FIRST WAVE WILL MOVE
INTO THE SRN FORECAST AREA NEAR SUNRISE THIS MORNING...MAKING ITS
WAY NORTH TO THE INTERSTATE 80 CORRIDOR BY 8 AM CDT. THE SHORT RANGE
MODELS...MOST NOTABLY THE NAM12...WARF...HRRR AND WNMM SOLNS CAME IN
SLOWER WITH THE ONSET OF PCPN THIS MORNING. AND INITIALLY CUT BACK
POPS IN THE NORTH...DELAYING THEM UNTIL LATER THIS MORNING.
HOWEVER...RADAR IMAGERY ACROSS KANSAS HAS THE LEADING EDGE OF THE
PRECIPITATION JUST OFF TO THE SOUTH OF A GOODLAND...TO HILL CITY
LINE. BASED ON THE FORWARD MOTION...THE LEADING EDGE OF THIS PCPN
SHOULD HIT THE FAR SRN CWA BY 6 AM CDT...AND WILL APPROACH THE
INTERSTATE 80 CORRIDOR BY 9 AM CDT. WITH THIS IN MIND...SLOWED DOWN
THE ONSET OF PCPN FROM THE INHERITED FCST...HOWEVER BROUGHT IT IN
SLIGHTLY EARLIER COMPARED TO THE SHORT RANGE MODELS...GIVEN THE
CURRENT RADAR RETURNS AND THE FORWARD SPEED OF THE AREA OF SHOWERS.
AS FOR THE THREAT FOR THUNDERSTORMS THIS MORNING...THE LATEST NAM
FORECAST LI`S ARE WELL ABOVE ZERO THIS MORNING...SO ACTIVITY WILL BE
LIMITED TO SHOWERS ONLY WITHOUT THE MENTION OF THUNDER. THIS AREA OF
PCPN WILL LIFT SLOWLY NORTH TODAY WITH A BRIEF REPRIEVE IN PCPN IN
THE SRN CWA LATER THIS AFTERNOON. BY EVENING...A SECONDARY LEAD
SHORTWAVE WILL PUSH INTO EASTERN COLORADO...INITIATING SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY WILL LIFT NEWD INTO THE SRN CWA LATER
THIS EVENING PER THE LATEST NAM12...WARF AND WNMM SOLNS WHICH HAVE A
CLUSTER OF THUNDERSTORMS PUSHING INTO THE AREA TONIGHT. ELEVATED
INSTABILITY WILL BE PRESENT OVERNIGHT AS H850 AND H800 CALCULATED
LI`S ARE WELL BELOW ZERO. INHERITED FCST HAD A MENTION OF THUNDER
TONIGHT AND SEE NO REASON TO TAKE IT OUT OF THE FCST ATTM. NOW AS
FOR THE THREAT FOR SEVERE STORMS...THE THREAT APPEARS LOW ATTM AS
THE BEST CAPES ARE WELL SOUTHWEST OF THE AREA WHERE SOME SUN AND SFC
HEATING TAKES PLACE. ALSO WITH THE CWA UNDER A VEIL OF CLOUD COVER
TODAY...CONDS WILL BE FAIRLY STABLE AT THE SFC...THUS NO TSRAS ARE
EXPECTED FOR LATE THIS AFTERNOON. AS MENTIONED EARLIER...ELEVATED
INSTABILITY WILL INCREASE OVERNIGHT PER H85 AND H80 NEG LI`S. WITH
THIS IN MIND...INSERTED A MENTION OF THUNDER...ESPECIALLY IN THE
SOUTH AND WEST. IN ADDITION TO THE THREAT FOR THUNDERSTORMS...PATCHY
FOG WILL BE POSSIBLE IN THE CENTRAL AND SOUTH. NUMERICAL
GUIDANCE...AS WELL AS THE SREF VISIBILITY FCST INDICATES A DECENT
THREAT FOR PATCHY FOG TONIGHT AFTER 06Z. WITH THIS IN MIND...DECIDED
TO LEAVE IN A MENTION OF PATCHY FOG OVERNIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI MAY 22 2015

IT APPEARS THAT SATURDAY WILL SEE LITTLE IF ANY SUNSHINE ACROSS THE
AREA. LOW LEVEL MOISTURE WILL BE INCREASING THROUGH THE DAY...AND
STRATUS SHOULD REMAIN LOCKED IN WITH EAST TO SOUTHEAST LOW LEVEL
UPSLOPE FLOW. EXPECT THAT A FEW SHOWERS AND THUNDERSTORMS MAY
OCCUR...BUT THESE SHOULD BE SCATTERED AT BEST AS MID LEVEL DRY AIR
PASSES OVERHEAD IN THE WAKE OF FRIDAY NIGHTS DISTURBANCE. THIS MID
LEVEL DRY AIR ABOVE THE SATURATED LOWER LEVELS COULD LEAD TO PATCHY
DRIZZLE...AND WILL INCLUDE IN SATURDAY MORNING FORECAST. AS
MENTIONED WITH LITTLE SUNSHINE EXPECTED...EXPECT A RATHER COOL DAY
WITH MOST HIGHS IN THE LOWER 60S.

A SIGNIFICANT PV ANOMALY WILL EJECT NORTHEAST THROUGH THE PLAINS ON
THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW SATURDAY NIGHT. THIS
WILL COINCIDE WITH A MODESTLY STRONG SOUTHERLY LOW LEVEL JET...AND
EXPECT A ROUND OF SHOWERS AND THUNDERSTORMS TO LIFT NORTHEAST ACROSS
THE AREA. THE THREAT FOR SEVERE LOOKS LOW...BUT SHEAR IS STRONG AND
SOME SMALL HAIL IS POSSIBLE WITH THE STRONGER STORMS. AN ISOLATED
SEVERE STORM WITH QUARTER SIZE HAIL CANNOT BE RULED OUT.

MODELS ARE COMING INTO BETTER AGREEMENT SUNDAY. GEFS MEAN HAS THE
CENTER OF THE UPPER LEVEL LOW NEAR DENVER SUNDAY MORNING. THE 22/00Z
NAM...GFS AND ECMWF MODELS ARE ALL IN A SIMILAR LOCATION WITH THE
UPPER LOW. CONFIDENCE IS INCREASING THAT A MID LEVEL DRY SLOT WILL
MOVE NORTHEAST ACROSS THE FORECAST AREA THROUGH THE DAY. WILL CARRY
THE HIGHER POPS DURING THE MORNING SUNDAY...AND TAPER TO JUST SLIGHT
CHANCE FOR ALL BUT THE PANHANDLE AND FAR WEST DURING THE AFTERNOON
AS THE MID LEVEL DRY SLOT MOVES OVERHEAD. A WARMER TREND IS ALSO
NOTED IN THE MODELS TONIGHT. NAM AND GFS SCOUR OUT SOME OF THE LOW
STRATUS CLOUDS DURING THE AFTERNOON...AND THE ECMWF IS COMING AROUND
TO THIS IDEA AS WELL. THIS COULD LEAD TO AT LEAST PARTLY SUNNY SKIES
SUNDAY AFTERNOON...AND HAVE BOOSTED HIGHS A BIT INTO THE LOWER TO
PERHAPS MID 70S FROM PORTIONS OF NORTH CENTRAL THROUGH SOUTHWEST
NEBRASKA. WILL KEEP THE MID TO UPPER 60S GOING FARTHER WEST IN
CLOSER PROXIMITY TO THE UPPER LEVEL LOW...WHERE MORE CLOUDS AND
BETTER CHANCES FOR SHOWERS AND STORMS WILL BE LOCATED.

SPEAKING OF STORMS...WILL HAVE TO AT LEAST EXPLORE THE IDEA OF A FEW
STRONG OR PERHAPS SEVERE THUNDERSTORMS LATER SUNDAY AFTERNOON INTO
SUNDAY EVENING. BOTH THE 22/00Z GFS AND NAM HAVE AN INVERTED TROUGH
EXTENDING NORTHEAST THROUGH THE FORECAST AREA UNDER THE DRY SLOT
FROM A SURFACE SLOW IN EASTERN COLORADO. SHOULD BE SOME FAIRLY STEEP
MID LEVEL LAPSE RATES OVERSPREADING THE AREA DURING THE AFTERNOON
AND EVENING...WHICH WILL HELP YIELD POTENTIALLY 1500 TO 2500 J/KG OF
SURFACE BASED CAPE. 0 TO 6 KM BULK SHEAR IS AROUND 30 KTS...A BIT
MORE THAN THAT IN THE GFS AND A BIT LESS IN THE NAM. IF ENOUGH
HEATING CAN TAKE PLACE TO REALIZE THE POTENTIAL CAPE...THEN SHEAR
WOULD BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS. BACKED WINDS
TO THE SOUTHEAST ARE EXPECTED EAST OF THE SURFACE TROUGH...OR
ROUGHLY EAST OF HIGHWAY 83...AND SUPERCELL STRUCTURES COULD
MATERIALIZE. THE THINKING IS THAT STORMS WILL DEVELOP ALONG THE
SURFACE TROUGH VERY LATE SUNDAY AFTERNOON OR EARLY SUNDAY EVENING
ALONG OR NEAR HIGHWAY 83. THE STORMS WILL BE AIDED BY LARGE SCALE
ASCENT FROM UPPER LOW WHICH WILL BE LOCATED JUST WEST OF THE
AREA...AND A SOUTH-SOUTHWESTERLY LOW LEVEL JET WHICH STRENGTHENS
SUNDAY EVENING. SO EXPECT STORMS TO CONGEAL INTO A LINE OR CLUSTER
AND MOVE NORTHEAST ACROSS NORTH CENTRAL AND CENTRAL NEBRASKA SUNDAY
NIGHT.

UPPER LOW WILL EJECT NORTHEAST THROUGH THE AREA MONDAY...WITH A
CONTINUED CHANCE FOR SHOWERS AND STORMS. ANOTHER LONG WAVE/CLOSED
LOW WILL DROP INTO THE NORTHERN ROCKIES TUESDAY AND DEVELOP SOUTH
THROUGH THE CENTRAL AND SOUTHERN ROCKIES MID TO LATE WEEK. SHOULD BE
A BROAD SOUTHWEST FLOW ALOFT ATOP A TROPICAL MARITIME AIRMASS ACROSS
THE CENTRAL AND SOUTHERN PLAINS...WITH MORE CHANCES FOR
THUNDERSTORMS. COVERAGE LOOKS SCATTERED THOUGH...WITH WARMER
TEMPERATURES EXPECTED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 345 AM CDT FRI MAY 22 2015

THE SOUTH PLATTE RIVER AT ROSCOE AND THE PLATTE RIVER
AT BRADY ARE EXPECTED TO BE AT MINOR FLOOD STAGE OVER THE NEXT
SEVERAL DAYS. ELEVATED RIVER LEVELS WILL CONTINUE ALONG THE SOUTH
PLATTE RIVER AT NORTH PLATTE...AS WELL AS THE NORTH PLATTE RIVER AT
LEWELLEN. RECENT HEAVY RAIN IN THE PANHANDLE AND NORTHEASTERN
COLORADO...ALONG WITH SNOWMELT FROM THE COLORADO ROCKIES...HAS LED
TO THE ELEVATED RIVER LEVELS. ABUNDANT RAIN IS FORECAST OVER THE
NEXT COUPLE OF DAYS...ESPECIALLY IN THE SOUTH AND NORTH PLATTE RIVER
BASINS WHICH WILL PROBABLY CONTRIBUTE TO ADDITIONAL RISES IN RIVER
LEVELS TOWARD THE END OF NEXT WEEK. BOTTOM LINE...RIVER LEVELS ALONG
THE NORTH AND ESPECIALLY THE SOUTH PLATTE RIVER WILL BE ELEVATED FOR
AT LEAST THE NEXT 2 TO 4 WEEKS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...POWER
HYDROLOGY...CLB








000
FXUS63 KLBF 220540
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 AM CDT FRI MAY 22 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN







000
FXUS63 KLBF 220540
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 AM CDT FRI MAY 22 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN







000
FXUS63 KLBF 220540
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 AM CDT FRI MAY 22 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1236 AM CDT FRI MAY 22 2015

CLOUDS WILL INCREASE FROM THE SOUTHWEST TONIGHT AND BEGIN TO LOWER
INTO MVFR CATEGORIES OVER THE SOUTHEAST NEBRASKA PANHANDLE AND
SOUTHWEST NEBRASKA. SCATTERED AREAS OF RAIN WILL BEGIN TO AFFECT KLBF
THROUGH MID MORNING. HAVE INCLUDED IN A TEMPO GROUP THROUGH 22/18Z
AND THEN WITH MORE CONFIDENCE HAVE MADE IT PREVAILING THROUGH THE
AFTERNOON. ENDED RAIN AT KLBF AFTER 23/00Z. KVTN WILL BE ON THE
NORTHERN EDGE OF THE PRECIPITATION SHIELD MOST OF THE DAY AND HAVE
INCLUDED CHANCES AFTER 23/00Z.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN








000
FXUS63 KLBF 212351 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
651 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 650 PM CDT THU MAY 21 2015

INCREASING CLOUDS FROM THE WEST OVER NIGHT WITH PRECIPITATION
BEGINNING OVER THE PANHANDLE AND SOUTHWEST NEBRASKA AFTER 12Z
22ND. SOUTHEAST WINDS INCREASING THROUGH THE DAY ON FRIDAY.
THROUGH THE DAY CIG HEIGHTS WILL GO FROM VFR TO MVFR IN LIGHT TO
MODERATE RAIN THROUGH THE AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN








000
FXUS63 KLBF 212351 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
651 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 650 PM CDT THU MAY 21 2015

INCREASING CLOUDS FROM THE WEST OVER NIGHT WITH PRECIPITATION
BEGINNING OVER THE PANHANDLE AND SOUTHWEST NEBRASKA AFTER 12Z
22ND. SOUTHEAST WINDS INCREASING THROUGH THE DAY ON FRIDAY.
THROUGH THE DAY CIG HEIGHTS WILL GO FROM VFR TO MVFR IN LIGHT TO
MODERATE RAIN THROUGH THE AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN








000
FXUS63 KLBF 212351 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
651 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 650 PM CDT THU MAY 21 2015

INCREASING CLOUDS FROM THE WEST OVER NIGHT WITH PRECIPITATION
BEGINNING OVER THE PANHANDLE AND SOUTHWEST NEBRASKA AFTER 12Z
22ND. SOUTHEAST WINDS INCREASING THROUGH THE DAY ON FRIDAY.
THROUGH THE DAY CIG HEIGHTS WILL GO FROM VFR TO MVFR IN LIGHT TO
MODERATE RAIN THROUGH THE AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN







000
FXUS63 KLBF 212351 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
651 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 650 PM CDT THU MAY 21 2015

INCREASING CLOUDS FROM THE WEST OVER NIGHT WITH PRECIPITATION
BEGINNING OVER THE PANHANDLE AND SOUTHWEST NEBRASKA AFTER 12Z
22ND. SOUTHEAST WINDS INCREASING THROUGH THE DAY ON FRIDAY.
THROUGH THE DAY CIG HEIGHTS WILL GO FROM VFR TO MVFR IN LIGHT TO
MODERATE RAIN THROUGH THE AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN







000
FXUS63 KLBF 212032
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
332 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1235 PM CDT THU MAY 21 2015

VFR CONDITIONS PREVAIL FOR MOST OF WESTERN AND NORTH CENTRAL
THROUGH THURSDAY EVENING. THE ONLY EXCEPTION IS FAR SOUTHWEST
NEBRASKA...INCLUDING KOGA AND KIML...WHERE A LOW STRATUS DECK IS
KEEPING CIGS NEAR MVFR LEVELS. THIS STRATUS DECK WILL ONLY
SLIGHTLY MOVE EAST DURING THE DAY...AND CONFIDENCE IS LOW THAT IT
WILL MAKE IT TO KLBF BEYOND JUST SCT SKY CONDITIONS OVER THE NEXT
6 TO 12 HOURS.

CONDITIONS BEGIN TO CHANGE OVERNIGHT AS PRECIPITATION ENTERS INTO
SOUTHWEST NEBRASKA. MVFR OR LOW CIGS ARE LIKELY BY FRIDAY MORNING
AT KLBF ALONG WITH -RA. VISBY AND CIGS MAY BE LOWER AT TIMES THAN
WHAT IS CURRENTLY INDICATED IN THE TAF...BUT CONFIDENCE IS TOO
LOW INCLUDE IN A GROUP AT THIS TIME. THE RAIN WILL ADVANCE
NORTHEAST DURING THE MORNING...POSSIBLY REACHING KVTN BY 18Z
FRIDAY.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...MARTIN
HYDROLOGY...MARTIN







000
FXUS63 KLBF 212032
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
332 PM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

AT 20Z A SHORTWAVE RIDGE AXIS ALOFT WAS POSITIONED THROUGH THE
NEBRASKA PANHANDLE AND EASTERN COLORADO...DOWNSTREAM FROM A LONGWAVE
TROUGH BUILDING INTO THE WESTERN CONUS. AT THE SURFACE AN AREA OF
HIGH PRESSURE WAS SLOWLY DRIFTING SOUTHEAST INTO CENTRAL NEBRASKA.
SOUTHERLY FLOW IN THE WAKE OF THE DEPARTING HIGH WAS TRANSPORTING
LOW TO MID LEVEL MOISTURE BACK INTO THE AREA...EVIDENT BY AN
EXPANSIVE STRATUS DECK FROM FAR SOUTHWEST NEBRASKA INTO THE
PANHANDLE.  DRIER AIR TO THE EAST AND ALOFT HAS BEEN SLOWING THE
EASTWARD ADVANCEMENT OF STRATUS THIS AFTERNOON AND EVEN CREATING A
FEW BREAKS IN THE CLOUDS. TEMPERATURES WERE IN THE 60S IN AREAS
EXPERIENCING SUNSHINE...WITH COOLER TEMPS IN THE 50S UNDERNEATH THE
CLOUDS.

A LEAD PV MAX CURRENTLY ROUNDING THE BASE OF THE LONGWAVE TROUGH
EJECTS NORTHEAST FROM THE BAJA OF CALIFORNIA AND TOWARD THE CENTRAL
PLAINS TONIGHT. MOISTURE TRANSPORT INCREASES AS PWATS NEAR 1 INCH
LOCALLY. A BROAD AREA OF PRECIPITATION WILL DEVELOP OVER COLORADO
AND MOVE NORTHEAST INTO THE CWA OVERNIGHT. WIDESPREAD DEFINITE POPS
COVER MUCH OF SOUTHWEST NEBRASKA THROUGH THE MORNING HOURS FRIDAY.
MODEL COMPUTED LI/S ARE POSITIVE BOTH AT THE SFC AND 800MB THROUGH
00Z SATURDAY...SO LEFT ANY MENTION OF THUNDER OUT OF THE SHORT TERM
PERIOD. MODELS SHOW THE PRIMARY AREA OF RAINFALL ADVANCING INTO THE
CENTRAL AND NORTHERN SANDHILLS BY THE AFTERNOON. BEHIND THE MAIN
BAND OF RAIN...MODEL SOUNDINGS SHOW PERSISTENT LIGHT RAIN/DRIZZLE AS
THE LOW LEVELS REMAIN SATURATED IN THE PRESENCE OF MOIST
SOUTHEASTERLY FLOW.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 331 PM CDT THU MAY 21 2015

FRIDAY NIGHT THROUGH SUNDAY...WINDS ALOFT AT 300 MB INCREASE TO
AROUND 80 KT AS AN UPPER LEVEL LOW MOVES EAST INTO THE CNTL ROCKIES
FRIDAY NIGHT. THE MODELS SUGGEST A WEAK DISTURBANCE WOULD LIFT
NORTHEAST THROUGH SWRN NEB SPAWNING A CLUSTER OF TSTMS WHICH WEAKEN
ACROSS SCNTL NEB AFTER MIDNIGHT. IN THE WAKE OF THE DISTURBANCE DRY
AIR WILL MOVE IN ALOFT. THE NAM AND SREF...MET AND MAV GUIDANCE SHOW
FOG DEVELOPING WHICH MIXES OUT DURING THE DAY SATURDAY AND RETURNS
AGAIN SATURDAY NIGHT. THE FOG FORECAST FOLLOWS THE 40 PERCENT
PROBABILITY OF LESS THAN 1 MILE VISIBILITY INDICATED IN THE SREF.

ANOTHER PERHAPS MORE ROBUST ROUND OF TSTMS IS EXPECTED TO DEVELOP
ACROSS NERN COLO SATURDAY AFTERNOON WHICH LIFTS NORTH THROUGH THE
FCST AREA SATURDAY NIGHT. THE UPPER LOW WILL BE MOVING THROUGH
COLO/WY IN THE EVENING PROVIDING SUPPORT. THE MODELS SUGGEST STORM
COVERAGE WOULD GROW UPSCALE IN A LINEAR MULTICELL ENVIRONMENT
DEVELOPING EAST ACROSS THE FCST AREA. THE BEST FORCING WOULD BE
ACROSS THE WRN NEB CLOSER TO THE UPPER LOW. THE LOCATION OF A WARM
FRONT...NERN COLO OR SWRN NEB...WILL DICTATE THE POTENTIAL FOR
SEVERE WEATHER. SPC FORECASTS NORTHEAST COLO FOR IGNITION. THUS
STORMS LIFTING INTO THE FCST AREA WOULD LIKELY BE ELEVATED HAIL
MAKERS. THE NAM SUGGESTS SWRN NEB FOR SFC BASED SEVERE STORM
DEVELOPMENT. IN THAT CASE WIND DAMAGE WOULD BE INCLUDED IN THE
SEVERE WEATHER THREAT.

1/3 TO 3/4 OF AN INCH OF RAIN IS EXPECTED FRIDAY NIGHT THROUGH
SUNDAY WITH HIGHEST AMOUNTS ALONG AND WEST OF HIGHWAY 61 AND LEAST
RAINFALL ALONG HIGHWAY 281. LOCALLY HIGHER TOTALS SHOULD BE
EXPECTED...ESPECIALLY WEST.

RAIN CHANCES CONTINUE SUNDAY ALTHOUGH NOTHING ORGANIZED IS INDICATED
IN THE MODELS. LAPSE RATES STEEPEN AS TEMPS AT H700MB RISE AND THE
UPPER LEVELS REMAIN COLD WITH THE APPROACHING UPPER LOW. THIS COULD
SUPPORT DIURNAL TSTM DEVELOPMENT.

OTHERWISE...THE MODELS ARE TRENDING COOLER SATURDAY FOR HIGHS IN THE
60S. A WARM FRONT MAY CAPTURE SWRN NEB PRODUCING HIGHS NEAR 70 OR
WARMER BUT THAT IS THE GFS/NAM SOLN. THE ECM SHOWS 50S EVERYWHERE
WHILE THE NAM SHOWS 50S NORTHWEST AND 70S SOUTHWEST. THE GEM SHOWS
60S EVERYWHERE. GIVEN THE LIGHT QPF AND MOISTURE IN THE ECM
850-700MB DRIZZLE MAY DEVELOP SATURDAY.

THE TEMPERATURE FORECAST SUNDAY IS UNUSUAL AGAIN WITH THE ECM AND
GEM SHOWING 50S AND 60S WHILE THE NAM AND GFS SHOW 60S AND 70S. THE
WARMER MODELS PARTIALLY CLEAR SKY COVER IN THE FCST AREA WHILE THE
COOL ONES LOCK IN THE OVERCAST. THE FORECAST LEANS TOWARD THE COOLER
CLOUDY SOLNS FOR HIGHS IN THE 60S TO NEAR 70.

SUNDAY NIGHT THROUGH THURSDAY...A SECOND LOBE OF COLD AIR ALOFT WILL
REINFORCE THE UPPER LEVEL LOW SUNDAY NIGHT SLOWING THE FILLING
PROCESS. THE REAL CULPRIT IS AN ANOMALOUS AMPLIFICATION OF THE AN
UPPER LEVEL RIDGE OFF THE FL COAST TO 592 DM BY MONDAY MORNING
FORMING A BLOCK WHICH KEEPS HEIGHTS LOW ACROSS THE WRN U.S.. BY
MONDAY MORNING H500MB TEMPS HAVE COOLED TO -16C.

A PORTION OF THE UPPER LEVEL LOW LIFTS NORTH SUNDAY NIGHT WHICH
PRESUMABLY PRODUCES ADDITIONAL SCATTERED TSTMS GIVEN THE DIURNAL
HEATING CYCLE FOR IGNITION. THE BEST CHANCE FOR RAIN WOULD APPEAR
SUNDAY NIGHT AND MONDAY. THEREAFTER AN UPPER LEVEL DISTURBANCE
MOVING THROUGH THURSDAY PRESENTS AN OPPORTUNITY FOR ORGANIZED TSTM
DEVELOPMENT. OTHERWISE DIURNAL HEATING WOULD APPEAR TO BE THE ONLY
FORCING FOR TSTM DEVELOPMENT AND POPS ARE ISOLATED OR LOW END
CHANCE. THE GFS AND GEF SHOW A DISTURBANCE COMING ACROSS THE ROCKIES
TUESDAY BUT THE ECM SHOWS IT ACROSS TEXAS AND THE MIDSOUTH. THE GEM
HAS NOTHING.

SFC LOW PRESSURE SHOULD REDEVELOP ON THE NRN HIGH PLAINS TUESDAY AND
MIGRATE THROUGH THE NRN PLAINS WEDNESDAY AND THURSDAY. A GRADUAL
WARMING TREND SHOULD DEVELOP WITH HIGHS RISING INTO THE 70S. ODDLY
THE GEF IS FASTER AND PULLS A COLD FRONT THROUGH THURSDAY. THE
TEMPERATURE FORECAST IS A BLEND OF THE WARMER GFS/ECM AND COOLER
BIAS CORRECTED/GEF DATA FOR HIGHS IN THE 70S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1235 PM CDT THU MAY 21 2015

VFR CONDITIONS PREVAIL FOR MOST OF WESTERN AND NORTH CENTRAL
THROUGH THURSDAY EVENING. THE ONLY EXCEPTION IS FAR SOUTHWEST
NEBRASKA...INCLUDING KOGA AND KIML...WHERE A LOW STRATUS DECK IS
KEEPING CIGS NEAR MVFR LEVELS. THIS STRATUS DECK WILL ONLY
SLIGHTLY MOVE EAST DURING THE DAY...AND CONFIDENCE IS LOW THAT IT
WILL MAKE IT TO KLBF BEYOND JUST SCT SKY CONDITIONS OVER THE NEXT
6 TO 12 HOURS.

CONDITIONS BEGIN TO CHANGE OVERNIGHT AS PRECIPITATION ENTERS INTO
SOUTHWEST NEBRASKA. MVFR OR LOW CIGS ARE LIKELY BY FRIDAY MORNING
AT KLBF ALONG WITH -RA. VISBY AND CIGS MAY BE LOWER AT TIMES THAN
WHAT IS CURRENTLY INDICATED IN THE TAF...BUT CONFIDENCE IS TOO
LOW INCLUDE IN A GROUP AT THIS TIME. THE RAIN WILL ADVANCE
NORTHEAST DURING THE MORNING...POSSIBLY REACHING KVTN BY 18Z
FRIDAY.

&&

.HYDROLOGY...
ISSUED AT 331 PM CDT THU MAY 21 2015

LITTLE CHANGE HAS BEEN OBSERVED OVER THE LAST 12 HOURS ALONG THE
SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA AS OF THURSDAY
AFTERNOON. RIVER LEVELS WILL SLOWLY RECEDE THROUGH THE END OF THE
WEEK BEFORE HOLDING STEADY WITH MINOR FLUCTUATIONS OVER THE WEEKEND.
RECENT RAINFALL IN THE UPSTREAM SOUTH PLATTE RIVER BASIN WILL BRING
ADDITIONAL RIVER LEVEL RISES FOR THE FIRST HALF OF NEXT
WEEK...HOWEVER THE CRESTS WILL NOT BE HIGHER THAN WHAT WAS
EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

ADDITIONAL RAINFALL CHANCES OVER THE NEXT WEEK AND ABOVE NORMAL LATE
SEASON SNOW PACK IN THE UPPER REACHES OF THE RIVER BASIN WILL PROMOTE
ELEVATED FLOWS ALONG THE SOUTH PLATTE RIVER IN SOUTHWEST NEBRASKA
THROUGH AT LEAST THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...MARTIN
HYDROLOGY...MARTIN








000
FXUS63 KLBF 211740
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 PM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1235 PM CDT THU MAY 21 2015

VFR CONDITIONS PREVAIL FOR MOST OF WESTERN AND NORTH CENTRAL
THROUGH THURSDAY EVENING. THE ONLY EXCEPTION IS FAR SOUTHWEST
NEBRASKA...INCLUDING KOGA AND KIML...WHERE A LOW STRATUS DECK IS
KEEPING CIGS NEAR MVFR LEVELS. THIS STRATUS DECK WILL ONLY
SLIGHTLY MOVE EAST DURING THE DAY...AND CONFIDENCE IS LOW THAT IT
WILL MAKE IT TO KLBF BEYOND JUST SCT SKY CONDITIONS OVER THE NEXT
6 TO 12 HOURS.

CONDITIONS BEGIN TO CHANGE OVERNIGHT AS PRECIPITATION ENTERS INTO
SOUTHWEST NEBRASKA. MVFR OR LOW CIGS ARE LIKELY BY FRIDAY MORNING
AT KLBF ALONG WITH -RA. VISBY AND CIGS MAY BE LOWER AT TIMES THAN
WHAT IS CURRENTLY INDICATED IN THE TAF...BUT CONFIDENCE IS TOO
LOW INCLUDE IN A GROUP AT THIS TIME. THE RAIN WILL ADVANCE
NORTHEAST DURING THE MORNING...POSSIBLY REACHING KVTN BY 18Z
FRIDAY.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MARTIN
HYDROLOGY...CLB










000
FXUS63 KLBF 211740
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1240 PM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1235 PM CDT THU MAY 21 2015

VFR CONDITIONS PREVAIL FOR MOST OF WESTERN AND NORTH CENTRAL
THROUGH THURSDAY EVENING. THE ONLY EXCEPTION IS FAR SOUTHWEST
NEBRASKA...INCLUDING KOGA AND KIML...WHERE A LOW STRATUS DECK IS
KEEPING CIGS NEAR MVFR LEVELS. THIS STRATUS DECK WILL ONLY
SLIGHTLY MOVE EAST DURING THE DAY...AND CONFIDENCE IS LOW THAT IT
WILL MAKE IT TO KLBF BEYOND JUST SCT SKY CONDITIONS OVER THE NEXT
6 TO 12 HOURS.

CONDITIONS BEGIN TO CHANGE OVERNIGHT AS PRECIPITATION ENTERS INTO
SOUTHWEST NEBRASKA. MVFR OR LOW CIGS ARE LIKELY BY FRIDAY MORNING
AT KLBF ALONG WITH -RA. VISBY AND CIGS MAY BE LOWER AT TIMES THAN
WHAT IS CURRENTLY INDICATED IN THE TAF...BUT CONFIDENCE IS TOO
LOW INCLUDE IN A GROUP AT THIS TIME. THE RAIN WILL ADVANCE
NORTHEAST DURING THE MORNING...POSSIBLY REACHING KVTN BY 18Z
FRIDAY.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MARTIN
HYDROLOGY...CLB











000
FXUS63 KLBF 211149
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
649 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 648 AM CDT THU MAY 21 2015

EXPECT SCATTERED HIGH CLOUDS AROUND 25000 FT AGL TODAY WITH BROKEN
CIGS OF 10000 FT AGL SETTING IN TONIGHT. LIGHT RAIN WILL BE
POSSIBLE AT THE KLBF TERMINAL AFTER 09Z TONIGHT WITH CIGS DOWN TO
4000 FT AGL.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB








000
FXUS63 KLBF 211149
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
649 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 648 AM CDT THU MAY 21 2015

EXPECT SCATTERED HIGH CLOUDS AROUND 25000 FT AGL TODAY WITH BROKEN
CIGS OF 10000 FT AGL SETTING IN TONIGHT. LIGHT RAIN WILL BE
POSSIBLE AT THE KLBF TERMINAL AFTER 09Z TONIGHT WITH CIGS DOWN TO
4000 FT AGL.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB







000
FXUS63 KLBF 211149
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
649 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 648 AM CDT THU MAY 21 2015

EXPECT SCATTERED HIGH CLOUDS AROUND 25000 FT AGL TODAY WITH BROKEN
CIGS OF 10000 FT AGL SETTING IN TONIGHT. LIGHT RAIN WILL BE
POSSIBLE AT THE KLBF TERMINAL AFTER 09Z TONIGHT WITH CIGS DOWN TO
4000 FT AGL.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB







000
FXUS63 KLBF 211149
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
649 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 648 AM CDT THU MAY 21 2015

EXPECT SCATTERED HIGH CLOUDS AROUND 25000 FT AGL TODAY WITH BROKEN
CIGS OF 10000 FT AGL SETTING IN TONIGHT. LIGHT RAIN WILL BE
POSSIBLE AT THE KLBF TERMINAL AFTER 09Z TONIGHT WITH CIGS DOWN TO
4000 FT AGL.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...CLB
HYDROLOGY...CLB








000
FXUS63 KLBF 210902
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
402 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1247 AM CDT THU MAY 21 2015

SKIES CONTINUE TO CLEAR OVER ALL BUT THE SOUTHERN NEBRASKA PANHANDLE
AND SOUTHWEST NEBRASKA WHERE SOME MVFR CONDITIONS CEILINGS ARE
PRESENT. MVFR SHOULD GIVE WAY TO VFR CONDITIONS WITH SOME INCREASING
CLOUDS FROM NORTHEAST COLORADO. WINDS WILL SHIFT TO THE SOUTHEAST
LATE THIS MORNING OVER THE WESTERN NEBRASKA SANDHILLS AND SOUTHWEST
NEBRASKA.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...POWER
HYDROLOGY...CLB





000
FXUS63 KLBF 210902
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
402 AM CDT THU MAY 21 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT THU MAY 21 2015

H5 ANALYSIS TONIGHT HAS A BROAD AREA OF LOW PRESSURE OFF
THE COAST OF CALIFORNIA WITH A TROUGH EXTENDING SWD TO OFF THE COAST
OF BAJA CALIFORNIA. DOWNSTREAM OF THE TROUGH...LOW AMPLITUDE RIDGING
WAS NOTED FROM NEW MEXICO...NWD INTO WYOMING...WHILE MAINLY ZONAL
FLOW EXTENDED ACROSS THE MIDWEST...OHIO VALLEY AND SERN STATES. AT
THE SURFACE...HIGH PRESSURE HAD NOSED INTO NORTHWESTERN NEBRASKA
OVERNIGHT...AND HAS LED TO CLEARING SKIES ACROSS NORTH
CENTRAL...CENTRAL AND EASTERN NEBRASKA. LOWER CLOUDS HAVE HUNG ON
ACROSS THE SWRN CWA OVERNIGHT...ROUGHLY SOUTH OF A LINE FROM
OSHKOSH...TO PAXTON...TO HAYES CENTER. SOME HIGHER CLOUDS HAVE
PUSHED INTO THE REMAINDER OF SWRN NEBRASKA...AND HAS KEPT TEMPS
HITTING THE LOWER 30S AS OF 3 AM CDT. FURTHER NORTH AND WEST...LOWER
30S WERE NOTED ACROSS THE NWRN CWA...IN CLOSE PROXIMITY TO THE
SURFACE HIGH. SO FAR...THE AREAL COVERAGE OF THE FROST ADVISORY IS
ON TRACK ATTM AND WILL BE RE EVALUATED NEAR FORECAST ISSUANCE.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT THU MAY 21 2015

THE MAIN FORECAST CHALLENGES ARE
TEMPERATURES TODAY AND THE EFFECTS OF RESIDUAL CLOUD COVER ON
THEM...AS WELL AS THE THREAT FOR RAIN IN THE SW AND SERN PANHANDLE
OVERNIGHT TONIGHT. FOR TODAY...HIGH PRESSURE WILL BUILD SOUTHEAST
INTO MISSOURI THIS AFTERNOON...RESULTING IN A WIND SHIFT TO THE
SOUTH ACROSS THE WESTERN HALF OF THE FORECAST AREA. THIS SHIFT WILL
INCREASE LOW LEVEL MOISTURE TOWARD THE END OF THE DAY INTO TONIGHT
WITH DEW POINTS REACHING THE LOWER 40S OVERNIGHT TONIGHT.
TEMPERATURES TODAY WILL GENERALLY BE IN THE LOWER TO MID 60S WITH
THE WARMEST READINGS EXPECTED IN THE NORTHEASTERN CWA...WHERE CLEAR
SKIES AND THE DRIEST AIRMASS RESIDES. ACROSS SWRN PORTIONS OF THE
CWA...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH INCREASING CLOUDS
EXPECTED LATE AFTERNOON AS A SHORTWAVE APPROACHES THE SRN ROCKIES
AND SRN PLAINS. FOR TONIGHT...THE BEFORE MENTIONED SHORTWAVE WILL
LIFT NORTHEAST WITH THE H5 FLOW INTO EASTERN COLORADO AND WESTERN
KS. THIS FEATURE WILL APPROACH SWRN NEBRASKA OVERNIGHT. CROSS
SECTIONS INDICATE A DECENT SHOT OF MID LEVEL MOISTURE MOVING NORTH
INTO SWRN NEBRASKA OVERNIGHT WITH DECENT MID LEVEL LIFT COMMENCING
AFTER 06Z FRIDAY. INHERITED FORECAST HAD A GOOD HANDLE ON THE POPS
TONIGHT...AND HAVE ONLY SLIGHTLY SLOWED DOWN THE ONSET OF PCPN BASED
ON THE LATEST MODEL TRENDS. THE NAM12...GFS...WARF...AND NMM
GENERALLY KEEP PCPN OUT OF THE SWRN CWA UNTIL AFTER 06Z FRIDAY. BY
12Z FRIDAY...THE PRECIPITATION SHIELD APPROACHES THE INTERSTATE 80
AND HIGHWAY 26 CORRIDOR. HAVE LEFT PTYPES AS ALL RAIN AS WAS THE
CASE WITH THE INHERITED FCST. LIFTED INDICES...BOTH SURFACE
BASED...AS WELL AS ELEVATED...ARE WELL ABOVE ZERO TONIGHT...SO
THUNDER IS NOT EXPECTED ATTM. WITH INCREASING CLOUDS IN THE CENTRAL
AND NORTH...AND PRECIPITATION EXPECTED IN THE SOUTH AND
SOUTHWEST...OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER 40S.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM CDT THU MAY 21 2015

NEXT LONG WAVE TROUGH/CLOSED LOW WILL BE MOVING ONSHORE THE WEST
COAST FRIDAY. A LEAD SHORTWAVE WILL BE MOVING THOUGH THE AREA AHEAD
OF THIS FEATURE FRIDAY INTO FRIDAY NIGHT. ISENTROPIC LIFT/MID LEVEL
WARM AIR ADVECTION WILL BE WELL UNDERWAY BY FRIDAY MORNING. GFS AND
ECMWF CONTINUE TO BE MORE AGGRESSIVE WITH THE RAIN AND QPF AMOUNTS
ACROSS SOUTHWEST NEBRASKA FRIDAY MORNING. THE NAM CONTINUES TO BE
THE DRIER MODEL SOLUTION...AND AN INVESTIGATION OF THE NAM BUFFER
SOUNDING HINTS AT SOME DRY AIR AROUND 750MB EARLY IN THE MORNING.
THIS LAYER SATURATES COMPLETELY BY MID MORNING THOUGH...AND THE
LATEST 21/00Z NAM IS NOT QUITE AS AGGRESSIVE WITH HOLDING ON TO THE
DRY AIR AS PREVIOUS RUNS WERE...AND IS NOW GENERATING MORE QPF THAN
PREVIOUS RUNS AS A RESULT. THE GOING FORECAST ALREADY HAD
CATEGORICAL/DEFINITE POPS FOR FRIDAY MORNING ACROSS SOUTHWEST
NEBRASKA...AND SEE NO REASON TO LOWER THOSE...ESPECIALLY NOW THAT
THE NAM IS TRENDING A BIT WETTER. OTHERWISE ANOTHER CHILLY DAY WITH
THE CLOUDS AND PRECIP...BUT NOT AS CHILLY AS THE PREVIOUS RAIN EVENT
WE HAD ON MONDAY...AS THE 850MB TEMPS WILL BE ABOUT 5C WARMER THIS
TIME AROUND. GENERALLY EXPECT LOWER TO MID 50S IN THE RAINY AREAS OF
SOUTHWEST NEBRASKA...TO THE LOWER AND MID 60S ACROSS EASTERN
PORTIONS OF NORTH CENTRAL NEBRASKA WHERE THE RAIN WILL HOLD OFF TILL
LATE IN THE AFTERNOON.

FOR FRIDAY NIGHT THROUGH THE WEEKEND...MODELS UNFORTUNATELY ARE NOT
IN VERY GOOD AGREEMENT IN THE HANDLING OF THE WESTERN CONUS LONG
WAVE TROUGH/CLOSED LOW. OVERALL IT DOES NOT LOOK LIKE A COMPLETE
RAIN OUT THIS WEEKEND. CONTINUES TO BE HARD TO NAIL DOWN WHEN AND
WHERE THE BEST CHANCE FOR PRECIPITATION WILL BE...AS EACH MODEL HAS
IT/S OWN IDEA. THE BEST CHANCE APPEARS TO BE SATURDAY NIGHT AS A
FAIRLY POTENT MID LEVEL DISTURBANCE ROTATES NORTH THROUGH THE AREA
ON THE EASTERN PERIPHERY OF THE CLOSED UPPER LOW WHICH WILL BE
LOCATED NEAR NORTHWEST COLORADO BY THIS TIME. SUNDAY INTO
MONDAY...THE GEFS MEAN KEEPS THE UPPER SYSTEM CLOSED AS IT TRACKS
ACROSS SOUTH DAKOTA INTO NORTHERN MINNESOTA. THE OPERATIONAL GFS
AND ECMWF ARE MUCH SLOWER AND HOLD THE MAIN UPPER LEVEL SYSTEM BACK
IN THE ROCKIES. WITH ALL THE MODEL DIFFERENCES...HAVE TRIED TO TREND
POPS DOWN FOR THE WEEKEND OVERALL. MODELS ARE REALLY NOT GENERATING
A WHOLE LOT OF QPF AT ANY ONE TIME...AND MY THINKING IS THAT IT WILL
BE MORE OF A SCATTERED MID LEVEL WARM AIR ADVECTION TYPE PRECIP
EVENT...AS NO REAL FOCUS FOR ANY ONE AREA TO RECEIVE CONCENTRATED
HEAVY RAINFALL. THIS COULD CHANGE AS MODELS EVENTUALLY WILL HAVE TO
COME INTO BETTER AGREEMENT...AND WILL WATCH THIS CLOSELY. ONE MAJOR
DIFFERENCE IN THE MODELS IS ON SUNDAY. THE 21/00Z GFS INSISTS THAT A
SURFACE TROUGH WILL MOVE EAST INTO THE FORECAST AREA...WITH
INCREASING INSTABILITY AND POSSIBLE STRONGER THUNDERSTORMS. THE
21/00Z ECMWF WILL HAVE NONE OF THIS...AND KEEPS A BROAD COOLER/MOIST
SOUTHEAST TO EAST FLOW WITH LOW CLOUDS SOCKED IN. WILL CONTINUE TO
MONITOR THE LATEST MODEL TRENDS AND HOPEFULLY BEGIN TO SEE SOME
BETTER AGREEMENT.

WITH THE POOR MODEL AGREEMENT ALREADY SEEN BY SUNDAY AND
MONDAY...TUESDAY AND WEDNESDAY NOT EASY TO FORECAST GIVEN EVEN
FARTHER INTO THE FUTURE. OVERALL...WOULD APPEAR THAT RICH LOW LEVEL
GULF MOISTURE WILL BECOME ESTABLISHED EAST OF THE ROCKIES BY THIS
POINT. BUT TIMING ON ANY DISTURBANCE AND SURFACE BOUNDARY TO FOCUS
CONVECTION JUST CANNOT BE DETERMINED AT THIS POINT.
NEVERTHELESS...PATTERN RECOGNITION WOULD SUGGEST AT LEAST SOME
CHANCE FOR T-STORMS ALONG WITH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1247 AM CDT THU MAY 21 2015

SKIES CONTINUE TO CLEAR OVER ALL BUT THE SOUTHERN NEBRASKA PANHANDLE
AND SOUTHWEST NEBRASKA WHERE SOME MVFR CONDITIONS CEILINGS ARE
PRESENT. MVFR SHOULD GIVE WAY TO VFR CONDITIONS WITH SOME INCREASING
CLOUDS FROM NORTHEAST COLORADO. WINDS WILL SHIFT TO THE SOUTHEAST
LATE THIS MORNING OVER THE WESTERN NEBRASKA SANDHILLS AND SOUTHWEST
NEBRASKA.

&&

.HYDROLOGY...
ISSUED AT 400 AM CDT THU MAY 21 2015

MINOR FLOODING IS EXPECTED TO CONTINUE ALONG THE SOUTH
PLATTE RIVER AT ROSCOE...AND ALONG THE MAINSTEM OF THE PLATTE RIVER
AT BRADY FOR THE NEXT SEVERAL DAYS. AT NORTH PLATTE...THE SOUTH PLATTE
RIVER IS EXPECTED TO REMAIN BELOW THE FLOOD STAGE OF 13.0 FEET FOR
THE FORESEEABLE FUTURE. HOWEVER...THE RIVER IS EXPECTED TO REMAIN IN
THE 11.0 TO 12.3 RANGE OVER THE NEXT SEVERAL DAYS. FLUCTUATIONS IN
RIVER LEVELS WILL REMAIN POSSIBLE OVER THE NEXT SEVERAL DAYS...AS
RAIN IS FORECASTED THIS WEEKEND FOR ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA...AS WELL AS OVER THE SOUTH PLATTE RIVER BASIN IN
NORTHEASTERN COLORADO.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...POWER
HYDROLOGY...CLB






000
FXUS63 KLBF 210548
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1248 AM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

AT 20Z AN UPPER LEVEL SHORTWAVE WAS SLOWLY MOVING ACROSS THE
NORTHERN PLAINS...WITH WIDESPREAD CLOUD COVER PRESENT OVER THE STATE
OF NEBRASKA. WEAK COLD AIR ADVECTION IN THE 850MB TO 700MB LAYER WAS
PROMOTING STEEP LAPSE RATES AND THE DEVELOPMENT OF ISOLATED RAIN
SHOWERS THIS AFTERNOON...GENERALLY FROM NORTH PLATTE TO THEDFORD AND
POINTS EAST. THIS ACTIVITY WILL DIMINISH BY THE EVENING HOURS. DRIER
AIR AND CLEARING SKIES WILL BEGIN TO MOVE INTO NORTHERN NEBRASKA BY
SUNSET AND STEADILY ADVANCE SOUTH. THE CLEARING SKIES COMBINED WITH
SFC HIGH PRESSURE WILL SET THE STAGE FOR ANOTHER COOL NIGHT OVER THE
FORECAST AREA AND THE POTENTIAL FOR FROST. LOWEST TEMPERATURE
READINGS NEAR TO JUST BELOW FREEZING WILL OCCUR OVER THE CENTRAL
/NORTHERN SANDHILLS AND WESTWARD INTO THE NORTHEAST PANHANDLE. A
FROST ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO EARLY THURSDAY
MORNING TO COVER THIS AREA. A FEW SPOTS WHERE REMNANT SNOW COVER
STILL REMAINS MAY DROP BELOW 30 DEGREES TONIGHT...BUT THIS SHOULD BE
ISOLATED. MORE UNCERTAINTY REMAINS WITH RESPECT TO HOW FAR SOUTH THE
CLEARING WILL ADVANCE. AT THIS TIME MODEL CONSENSUS KEEPS THE I-80
CORRIDOR AND POINTS SOUTH UNDERNEATH SOME MID TO LOW LEVEL CLOUDS
THROUGH THE NIGHT...WHICH WOULD KEEP TEMPERATURES ABOVE FREEZING.

WARMER CONDITIONS...ALBEIT STILL BELOW NORMAL...ARE IN STORE FOR
TOMORROW AS A TRANSIENT SHORTWAVE RIDGE MOVES OVER THE HIGH PLAINS.
THE RETURN OF SOUTHERLY FLOW IN THE MID-LEVELS WILL BEGIN TO ADVECT
MOISTURE BACK OVER SOUTHWEST NEBRASKA. ANY STUBBORN CLOUD COVER WILL
KEEP TEMPERATURES DOWN A FEW DEGREES...SO EXPECTING THE WARMEST
READINGS IN THE UPPER 60S IN THE NORTHEAST PART OF THE CWA.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

THURSDAY NIGHT THROUGH SATURDAY...A WELL ADVERTISED H700 MB WARM
FRONT WILL LIFT NORTH THROUGH THE FCST AREA THROUGHOUT THE DAY
FRIDAY BEGINNING IN THE SOUTHWEST AFTER 06Z THURSDAY NIGHT.

THE RAIN FORECAST FRIDAY NIGHT AND SATURDAY IS UNCERTAIN GIVEN THE
DRY AIR MOVING IN ALOFT BEHIND THE WARM FRONT. THE MOISTURE BELOW
700 MB REMAINS IN PLACE...ESPECIALLY BELOW H850 MB. THUS OVERCAST
SKIES WOULD CONTINUE FRIDAY NIGHT AND SATURDAY.

WITH THE APPROACH OF A DEEP UPPER LOW...CURRENTLY OFF THE WEST
COAST...LAPSE RATES STEEPEN AFTER MIDNIGHT FRIDAY AND CONTINUE
THROUGH SATURDAY. MOISTURE INCREASES WITH PWAT APPROACHING OR
EXCEEDING 1 INCH. THUS K INDICES INCREASE TO OVER 30C AND 750 MB
COMPUTED CAPE INCREASES ACCORDING SIGNALING THUNDERSTORM POTENTIAL.

THE RAIN ASSOCIATED WITH THE H700 MB WARM FRONT FRIDAY APPEARS
MAINLY STRATIFORM WITH EMBEDDED SHOWERS. K INDICES ARE IN THE
20S...LESS THAN 30C.

TEMPERATURES FRIDAY RISE INTO JUST THE 50S UNDER THE RAIN SHIELD.
COOL AIR CONTINUES TO CIRCULATE NORTHWEST AROUND THE HIGH CURRENTLY
IN PLACE ACROSS THE CNTL PLAINS. UPSLOPE WINDS...MOISTURE AND THE
COOL HIGH SHOULD PRODUCE THESE HIGHS.

CONVECTIVE RAIN CHANCES SATURDAY COULD PRODUCE A FEW STRONG OR
SEVERE STORMS...MAINLY ELEVATED. A SFC WARM FRONT IS FORECAST TO
LIFT NORTH TO NEAR INTERSTATE 80 LATE IN THE AFTERNOON. LAPSE RATES
FROM 850MB AND UP BECOME STEEP AND H300 MB WINDS INCREASE TO
70-100KT WHICH IS QUITE STRONG AND WELL WITHIN THE PARAMETERS FOR
SEVERE WEATHER. THE NAM SHOWS 800MB COMPUTED CAPE INCREASING TO 2800
J/KG ACROSS SWRN NEB AT 21Z SATURDAY AND CLOSE TO 2000 J/KG ALONG
INTERSTATE 80 AT 00Z SATURDAY EVENING.

THE BEST LIFT FOR THUNDERSTORMS FRIDAY NIGHT AND SATURDAY DEVELOPS
ACROSS KS COINCIDENT WITH A RAPID INCREASE IN PWAT. CONVECTIVE
DEVELOPMENT ACROSS KS AND WRN/NCNTL NEB PROBABLY DEVELOPS AS A
RESULT OF GRADUALLY STEEPENING LAPSE RATES AS THE UPPER LOW
APPROACHES VERSUS BRUTE FORCING.

1/3 TO LOCALLY 1/2 INCH OR MORE RAINFALL IS EXPECTED IN A 6 HOUR
PERIOD FRIDAY. POPS ARE DEFINITE AT 80 PERCENT. THEREAFTER...A SHARP
INCREASE IN ELEVATED INSTABILITY DEVELOPS LATE FRIDAY NIGHT
TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. POPS FRIDAY NIGHT
INCREASE TO 60 PERCENT AFTER DROPPING OFF FRIDAY EVENING. SCATTERED
POPS ARE IN PLACE SATURDAY. QPF TOTALS FRIDAY AND SATURDAY COULD BE
LOCALLY HEAVY. THE GFS SUGGESTED 1/2 ACROSS SWRN NEB LATE FRIDAY
NIGHT.

SATURDAY NIGHT THROUGH WEDNESDAY...THE UPPER LOW AND ATTENDANT SFC
LOW PRESSURE LIFTS THROUGH THE CNTL PLAINS SUNDAY PRESENTING THE
ONLY HONEST RAIN CHANCE THROUGH WEDNESDAY. THEREAFTER A DISTURBANCE
MOVES THROUGH KS MONDAY FOLLOWED BY A SECOND ONE THROUGH THE DAKOTAS
TUESDAY. RAIN CHANCES APPEAR ISOLATED AFTER SUNDAY BUT THIS COULD BE
RAISED DEPENDING ON THE TRACK OF THESE SYSTEMS.

THE GEF AND OTHER MODELS ARE SHOWING A WARMING TREND WITH SFC LOW
PRESSURE MIGRATING INTO NRN NEB/SRN SD BY WEDNESDAY. H850
TEMPERATURES WARM INTO TEENS TO NEAR 20C. THE BAIS CORRECTED DATA
KEEPS HIGHS IN THE 60S TO LOWER 70S WHILE THE DETERMINISTIC SOLNS
SHOW A SHARP RISE INTO THE 70S TO NEAR 80 TUESDAY AND WEDNESDAY. THE
FORECAST CALLS FOR 60S SUNDAY AND 70S MONDAY AND BEYOND. LATER
FORECAST MAY HAVE TO MARK UP HIGHS TUESDAY AND WEDNESDAY. THE GFS
SHOWS 75 TO 85 TUESDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1247 AM CDT THU MAY 21 2015

SKIES CONTINUE TO CLEAR OVER ALL BUT THE SOUTHERN NEBRASKA PANHANDLE
AND SOUTHWEST NEBRASKA WHERE SOME MVFR CONDITIONS CEILINGS ARE
PRESENT. MVFR SHOULD GIVE WAY TO VFR CONDITIONS WITH SOME INCREASING
CLOUDS FROM NORTHEAST COLORADO. WINDS WILL SHIFT TO THE SOUTHEAST
LATE THIS MORNING OVER THE WESTERN NEBRASKA SANDHILLS AND SOUTHWEST
NEBRASKA.

&&

.HYDROLOGY...
ISSUED AT 313 PM CDT WED MAY 20 2015

THE SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA CONTINUE TO
SLOWLY RECEDE AS OF WEDNESDAY AFTERNOON. ADDITIONAL MINOR REDUCTIONS
IN RIVER LEVELS WILL CONTINUE THROUGH THE NEXT 24 TO 48 HOURS BEFORE
HOLDING STEADY THROUGH THE WEEKEND. RECENT RAINFALL IN THE UPSTREAM
SOUTH PLATTE RIVER BASIN WILL BRING ADDITIONAL RIVER LEVEL RISES FOR
THE FIRST HALF OF NEXT WEEK...HOWEVER THE CRESTS SHOULD NOT BE
HIGHER THAN WHAT WAS EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

MORE SHOWERS AND THUNDERSTORMS ARE FORECAST WITHIN THE RIVER BASIN
LATER THIS WEEK. WHILE THE RAINFALL IS NOT EXPECTED TO RESULT IN
IMMEDIATE RISES ALONG THE RIVER...IT MAY BE A CONCERN FOR LOCAL
FLOOD MITIGATION EFFORTS DUE TO LOCALLY HEAVY RAINFALL RATES. THE
ADDITIONAL RAINFALL AND SNOW MELT RUNOFF FROM THE COLORADO FRONT
RANGE WILL KEEP ELEVATED FLOWS ON THE SOUTH PLATTE AND PLATTE RIVERS
IN SOUTHWEST NEBRASKA THROUGH THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN









000
FXUS63 KLBF 210548
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1248 AM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

AT 20Z AN UPPER LEVEL SHORTWAVE WAS SLOWLY MOVING ACROSS THE
NORTHERN PLAINS...WITH WIDESPREAD CLOUD COVER PRESENT OVER THE STATE
OF NEBRASKA. WEAK COLD AIR ADVECTION IN THE 850MB TO 700MB LAYER WAS
PROMOTING STEEP LAPSE RATES AND THE DEVELOPMENT OF ISOLATED RAIN
SHOWERS THIS AFTERNOON...GENERALLY FROM NORTH PLATTE TO THEDFORD AND
POINTS EAST. THIS ACTIVITY WILL DIMINISH BY THE EVENING HOURS. DRIER
AIR AND CLEARING SKIES WILL BEGIN TO MOVE INTO NORTHERN NEBRASKA BY
SUNSET AND STEADILY ADVANCE SOUTH. THE CLEARING SKIES COMBINED WITH
SFC HIGH PRESSURE WILL SET THE STAGE FOR ANOTHER COOL NIGHT OVER THE
FORECAST AREA AND THE POTENTIAL FOR FROST. LOWEST TEMPERATURE
READINGS NEAR TO JUST BELOW FREEZING WILL OCCUR OVER THE CENTRAL
/NORTHERN SANDHILLS AND WESTWARD INTO THE NORTHEAST PANHANDLE. A
FROST ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO EARLY THURSDAY
MORNING TO COVER THIS AREA. A FEW SPOTS WHERE REMNANT SNOW COVER
STILL REMAINS MAY DROP BELOW 30 DEGREES TONIGHT...BUT THIS SHOULD BE
ISOLATED. MORE UNCERTAINTY REMAINS WITH RESPECT TO HOW FAR SOUTH THE
CLEARING WILL ADVANCE. AT THIS TIME MODEL CONSENSUS KEEPS THE I-80
CORRIDOR AND POINTS SOUTH UNDERNEATH SOME MID TO LOW LEVEL CLOUDS
THROUGH THE NIGHT...WHICH WOULD KEEP TEMPERATURES ABOVE FREEZING.

WARMER CONDITIONS...ALBEIT STILL BELOW NORMAL...ARE IN STORE FOR
TOMORROW AS A TRANSIENT SHORTWAVE RIDGE MOVES OVER THE HIGH PLAINS.
THE RETURN OF SOUTHERLY FLOW IN THE MID-LEVELS WILL BEGIN TO ADVECT
MOISTURE BACK OVER SOUTHWEST NEBRASKA. ANY STUBBORN CLOUD COVER WILL
KEEP TEMPERATURES DOWN A FEW DEGREES...SO EXPECTING THE WARMEST
READINGS IN THE UPPER 60S IN THE NORTHEAST PART OF THE CWA.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

THURSDAY NIGHT THROUGH SATURDAY...A WELL ADVERTISED H700 MB WARM
FRONT WILL LIFT NORTH THROUGH THE FCST AREA THROUGHOUT THE DAY
FRIDAY BEGINNING IN THE SOUTHWEST AFTER 06Z THURSDAY NIGHT.

THE RAIN FORECAST FRIDAY NIGHT AND SATURDAY IS UNCERTAIN GIVEN THE
DRY AIR MOVING IN ALOFT BEHIND THE WARM FRONT. THE MOISTURE BELOW
700 MB REMAINS IN PLACE...ESPECIALLY BELOW H850 MB. THUS OVERCAST
SKIES WOULD CONTINUE FRIDAY NIGHT AND SATURDAY.

WITH THE APPROACH OF A DEEP UPPER LOW...CURRENTLY OFF THE WEST
COAST...LAPSE RATES STEEPEN AFTER MIDNIGHT FRIDAY AND CONTINUE
THROUGH SATURDAY. MOISTURE INCREASES WITH PWAT APPROACHING OR
EXCEEDING 1 INCH. THUS K INDICES INCREASE TO OVER 30C AND 750 MB
COMPUTED CAPE INCREASES ACCORDING SIGNALING THUNDERSTORM POTENTIAL.

THE RAIN ASSOCIATED WITH THE H700 MB WARM FRONT FRIDAY APPEARS
MAINLY STRATIFORM WITH EMBEDDED SHOWERS. K INDICES ARE IN THE
20S...LESS THAN 30C.

TEMPERATURES FRIDAY RISE INTO JUST THE 50S UNDER THE RAIN SHIELD.
COOL AIR CONTINUES TO CIRCULATE NORTHWEST AROUND THE HIGH CURRENTLY
IN PLACE ACROSS THE CNTL PLAINS. UPSLOPE WINDS...MOISTURE AND THE
COOL HIGH SHOULD PRODUCE THESE HIGHS.

CONVECTIVE RAIN CHANCES SATURDAY COULD PRODUCE A FEW STRONG OR
SEVERE STORMS...MAINLY ELEVATED. A SFC WARM FRONT IS FORECAST TO
LIFT NORTH TO NEAR INTERSTATE 80 LATE IN THE AFTERNOON. LAPSE RATES
FROM 850MB AND UP BECOME STEEP AND H300 MB WINDS INCREASE TO
70-100KT WHICH IS QUITE STRONG AND WELL WITHIN THE PARAMETERS FOR
SEVERE WEATHER. THE NAM SHOWS 800MB COMPUTED CAPE INCREASING TO 2800
J/KG ACROSS SWRN NEB AT 21Z SATURDAY AND CLOSE TO 2000 J/KG ALONG
INTERSTATE 80 AT 00Z SATURDAY EVENING.

THE BEST LIFT FOR THUNDERSTORMS FRIDAY NIGHT AND SATURDAY DEVELOPS
ACROSS KS COINCIDENT WITH A RAPID INCREASE IN PWAT. CONVECTIVE
DEVELOPMENT ACROSS KS AND WRN/NCNTL NEB PROBABLY DEVELOPS AS A
RESULT OF GRADUALLY STEEPENING LAPSE RATES AS THE UPPER LOW
APPROACHES VERSUS BRUTE FORCING.

1/3 TO LOCALLY 1/2 INCH OR MORE RAINFALL IS EXPECTED IN A 6 HOUR
PERIOD FRIDAY. POPS ARE DEFINITE AT 80 PERCENT. THEREAFTER...A SHARP
INCREASE IN ELEVATED INSTABILITY DEVELOPS LATE FRIDAY NIGHT
TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. POPS FRIDAY NIGHT
INCREASE TO 60 PERCENT AFTER DROPPING OFF FRIDAY EVENING. SCATTERED
POPS ARE IN PLACE SATURDAY. QPF TOTALS FRIDAY AND SATURDAY COULD BE
LOCALLY HEAVY. THE GFS SUGGESTED 1/2 ACROSS SWRN NEB LATE FRIDAY
NIGHT.

SATURDAY NIGHT THROUGH WEDNESDAY...THE UPPER LOW AND ATTENDANT SFC
LOW PRESSURE LIFTS THROUGH THE CNTL PLAINS SUNDAY PRESENTING THE
ONLY HONEST RAIN CHANCE THROUGH WEDNESDAY. THEREAFTER A DISTURBANCE
MOVES THROUGH KS MONDAY FOLLOWED BY A SECOND ONE THROUGH THE DAKOTAS
TUESDAY. RAIN CHANCES APPEAR ISOLATED AFTER SUNDAY BUT THIS COULD BE
RAISED DEPENDING ON THE TRACK OF THESE SYSTEMS.

THE GEF AND OTHER MODELS ARE SHOWING A WARMING TREND WITH SFC LOW
PRESSURE MIGRATING INTO NRN NEB/SRN SD BY WEDNESDAY. H850
TEMPERATURES WARM INTO TEENS TO NEAR 20C. THE BAIS CORRECTED DATA
KEEPS HIGHS IN THE 60S TO LOWER 70S WHILE THE DETERMINISTIC SOLNS
SHOW A SHARP RISE INTO THE 70S TO NEAR 80 TUESDAY AND WEDNESDAY. THE
FORECAST CALLS FOR 60S SUNDAY AND 70S MONDAY AND BEYOND. LATER
FORECAST MAY HAVE TO MARK UP HIGHS TUESDAY AND WEDNESDAY. THE GFS
SHOWS 75 TO 85 TUESDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1247 AM CDT THU MAY 21 2015

SKIES CONTINUE TO CLEAR OVER ALL BUT THE SOUTHERN NEBRASKA PANHANDLE
AND SOUTHWEST NEBRASKA WHERE SOME MVFR CONDITIONS CEILINGS ARE
PRESENT. MVFR SHOULD GIVE WAY TO VFR CONDITIONS WITH SOME INCREASING
CLOUDS FROM NORTHEAST COLORADO. WINDS WILL SHIFT TO THE SOUTHEAST
LATE THIS MORNING OVER THE WESTERN NEBRASKA SANDHILLS AND SOUTHWEST
NEBRASKA.

&&

.HYDROLOGY...
ISSUED AT 313 PM CDT WED MAY 20 2015

THE SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA CONTINUE TO
SLOWLY RECEDE AS OF WEDNESDAY AFTERNOON. ADDITIONAL MINOR REDUCTIONS
IN RIVER LEVELS WILL CONTINUE THROUGH THE NEXT 24 TO 48 HOURS BEFORE
HOLDING STEADY THROUGH THE WEEKEND. RECENT RAINFALL IN THE UPSTREAM
SOUTH PLATTE RIVER BASIN WILL BRING ADDITIONAL RIVER LEVEL RISES FOR
THE FIRST HALF OF NEXT WEEK...HOWEVER THE CRESTS SHOULD NOT BE
HIGHER THAN WHAT WAS EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

MORE SHOWERS AND THUNDERSTORMS ARE FORECAST WITHIN THE RIVER BASIN
LATER THIS WEEK. WHILE THE RAINFALL IS NOT EXPECTED TO RESULT IN
IMMEDIATE RISES ALONG THE RIVER...IT MAY BE A CONCERN FOR LOCAL
FLOOD MITIGATION EFFORTS DUE TO LOCALLY HEAVY RAINFALL RATES. THE
ADDITIONAL RAINFALL AND SNOW MELT RUNOFF FROM THE COLORADO FRONT
RANGE WILL KEEP ELEVATED FLOWS ON THE SOUTH PLATTE AND PLATTE RIVERS
IN SOUTHWEST NEBRASKA THROUGH THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN








000
FXUS63 KLBF 210548
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1248 AM CDT THU MAY 21 2015

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

AT 20Z AN UPPER LEVEL SHORTWAVE WAS SLOWLY MOVING ACROSS THE
NORTHERN PLAINS...WITH WIDESPREAD CLOUD COVER PRESENT OVER THE STATE
OF NEBRASKA. WEAK COLD AIR ADVECTION IN THE 850MB TO 700MB LAYER WAS
PROMOTING STEEP LAPSE RATES AND THE DEVELOPMENT OF ISOLATED RAIN
SHOWERS THIS AFTERNOON...GENERALLY FROM NORTH PLATTE TO THEDFORD AND
POINTS EAST. THIS ACTIVITY WILL DIMINISH BY THE EVENING HOURS. DRIER
AIR AND CLEARING SKIES WILL BEGIN TO MOVE INTO NORTHERN NEBRASKA BY
SUNSET AND STEADILY ADVANCE SOUTH. THE CLEARING SKIES COMBINED WITH
SFC HIGH PRESSURE WILL SET THE STAGE FOR ANOTHER COOL NIGHT OVER THE
FORECAST AREA AND THE POTENTIAL FOR FROST. LOWEST TEMPERATURE
READINGS NEAR TO JUST BELOW FREEZING WILL OCCUR OVER THE CENTRAL
/NORTHERN SANDHILLS AND WESTWARD INTO THE NORTHEAST PANHANDLE. A
FROST ADVISORY HAS BEEN ISSUED FOR TONIGHT INTO EARLY THURSDAY
MORNING TO COVER THIS AREA. A FEW SPOTS WHERE REMNANT SNOW COVER
STILL REMAINS MAY DROP BELOW 30 DEGREES TONIGHT...BUT THIS SHOULD BE
ISOLATED. MORE UNCERTAINTY REMAINS WITH RESPECT TO HOW FAR SOUTH THE
CLEARING WILL ADVANCE. AT THIS TIME MODEL CONSENSUS KEEPS THE I-80
CORRIDOR AND POINTS SOUTH UNDERNEATH SOME MID TO LOW LEVEL CLOUDS
THROUGH THE NIGHT...WHICH WOULD KEEP TEMPERATURES ABOVE FREEZING.

WARMER CONDITIONS...ALBEIT STILL BELOW NORMAL...ARE IN STORE FOR
TOMORROW AS A TRANSIENT SHORTWAVE RIDGE MOVES OVER THE HIGH PLAINS.
THE RETURN OF SOUTHERLY FLOW IN THE MID-LEVELS WILL BEGIN TO ADVECT
MOISTURE BACK OVER SOUTHWEST NEBRASKA. ANY STUBBORN CLOUD COVER WILL
KEEP TEMPERATURES DOWN A FEW DEGREES...SO EXPECTING THE WARMEST
READINGS IN THE UPPER 60S IN THE NORTHEAST PART OF THE CWA.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 313 PM CDT WED MAY 20 2015

THURSDAY NIGHT THROUGH SATURDAY...A WELL ADVERTISED H700 MB WARM
FRONT WILL LIFT NORTH THROUGH THE FCST AREA THROUGHOUT THE DAY
FRIDAY BEGINNING IN THE SOUTHWEST AFTER 06Z THURSDAY NIGHT.

THE RAIN FORECAST FRIDAY NIGHT AND SATURDAY IS UNCERTAIN GIVEN THE
DRY AIR MOVING IN ALOFT BEHIND THE WARM FRONT. THE MOISTURE BELOW
700 MB REMAINS IN PLACE...ESPECIALLY BELOW H850 MB. THUS OVERCAST
SKIES WOULD CONTINUE FRIDAY NIGHT AND SATURDAY.

WITH THE APPROACH OF A DEEP UPPER LOW...CURRENTLY OFF THE WEST
COAST...LAPSE RATES STEEPEN AFTER MIDNIGHT FRIDAY AND CONTINUE
THROUGH SATURDAY. MOISTURE INCREASES WITH PWAT APPROACHING OR
EXCEEDING 1 INCH. THUS K INDICES INCREASE TO OVER 30C AND 750 MB
COMPUTED CAPE INCREASES ACCORDING SIGNALING THUNDERSTORM POTENTIAL.

THE RAIN ASSOCIATED WITH THE H700 MB WARM FRONT FRIDAY APPEARS
MAINLY STRATIFORM WITH EMBEDDED SHOWERS. K INDICES ARE IN THE
20S...LESS THAN 30C.

TEMPERATURES FRIDAY RISE INTO JUST THE 50S UNDER THE RAIN SHIELD.
COOL AIR CONTINUES TO CIRCULATE NORTHWEST AROUND THE HIGH CURRENTLY
IN PLACE ACROSS THE CNTL PLAINS. UPSLOPE WINDS...MOISTURE AND THE
COOL HIGH SHOULD PRODUCE THESE HIGHS.

CONVECTIVE RAIN CHANCES SATURDAY COULD PRODUCE A FEW STRONG OR
SEVERE STORMS...MAINLY ELEVATED. A SFC WARM FRONT IS FORECAST TO
LIFT NORTH TO NEAR INTERSTATE 80 LATE IN THE AFTERNOON. LAPSE RATES
FROM 850MB AND UP BECOME STEEP AND H300 MB WINDS INCREASE TO
70-100KT WHICH IS QUITE STRONG AND WELL WITHIN THE PARAMETERS FOR
SEVERE WEATHER. THE NAM SHOWS 800MB COMPUTED CAPE INCREASING TO 2800
J/KG ACROSS SWRN NEB AT 21Z SATURDAY AND CLOSE TO 2000 J/KG ALONG
INTERSTATE 80 AT 00Z SATURDAY EVENING.

THE BEST LIFT FOR THUNDERSTORMS FRIDAY NIGHT AND SATURDAY DEVELOPS
ACROSS KS COINCIDENT WITH A RAPID INCREASE IN PWAT. CONVECTIVE
DEVELOPMENT ACROSS KS AND WRN/NCNTL NEB PROBABLY DEVELOPS AS A
RESULT OF GRADUALLY STEEPENING LAPSE RATES AS THE UPPER LOW
APPROACHES VERSUS BRUTE FORCING.

1/3 TO LOCALLY 1/2 INCH OR MORE RAINFALL IS EXPECTED IN A 6 HOUR
PERIOD FRIDAY. POPS ARE DEFINITE AT 80 PERCENT. THEREAFTER...A SHARP
INCREASE IN ELEVATED INSTABILITY DEVELOPS LATE FRIDAY NIGHT
TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. POPS FRIDAY NIGHT
INCREASE TO 60 PERCENT AFTER DROPPING OFF FRIDAY EVENING. SCATTERED
POPS ARE IN PLACE SATURDAY. QPF TOTALS FRIDAY AND SATURDAY COULD BE
LOCALLY HEAVY. THE GFS SUGGESTED 1/2 ACROSS SWRN NEB LATE FRIDAY
NIGHT.

SATURDAY NIGHT THROUGH WEDNESDAY...THE UPPER LOW AND ATTENDANT SFC
LOW PRESSURE LIFTS THROUGH THE CNTL PLAINS SUNDAY PRESENTING THE
ONLY HONEST RAIN CHANCE THROUGH WEDNESDAY. THEREAFTER A DISTURBANCE
MOVES THROUGH KS MONDAY FOLLOWED BY A SECOND ONE THROUGH THE DAKOTAS
TUESDAY. RAIN CHANCES APPEAR ISOLATED AFTER SUNDAY BUT THIS COULD BE
RAISED DEPENDING ON THE TRACK OF THESE SYSTEMS.

THE GEF AND OTHER MODELS ARE SHOWING A WARMING TREND WITH SFC LOW
PRESSURE MIGRATING INTO NRN NEB/SRN SD BY WEDNESDAY. H850
TEMPERATURES WARM INTO TEENS TO NEAR 20C. THE BAIS CORRECTED DATA
KEEPS HIGHS IN THE 60S TO LOWER 70S WHILE THE DETERMINISTIC SOLNS
SHOW A SHARP RISE INTO THE 70S TO NEAR 80 TUESDAY AND WEDNESDAY. THE
FORECAST CALLS FOR 60S SUNDAY AND 70S MONDAY AND BEYOND. LATER
FORECAST MAY HAVE TO MARK UP HIGHS TUESDAY AND WEDNESDAY. THE GFS
SHOWS 75 TO 85 TUESDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1247 AM CDT THU MAY 21 2015

SKIES CONTINUE TO CLEAR OVER ALL BUT THE SOUTHERN NEBRASKA PANHANDLE
AND SOUTHWEST NEBRASKA WHERE SOME MVFR CONDITIONS CEILINGS ARE
PRESENT. MVFR SHOULD GIVE WAY TO VFR CONDITIONS WITH SOME INCREASING
CLOUDS FROM NORTHEAST COLORADO. WINDS WILL SHIFT TO THE SOUTHEAST
LATE THIS MORNING OVER THE WESTERN NEBRASKA SANDHILLS AND SOUTHWEST
NEBRASKA.

&&

.HYDROLOGY...
ISSUED AT 313 PM CDT WED MAY 20 2015

THE SOUTH PLATTE AND PLATTE RIVERS IN SOUTHWEST NEBRASKA CONTINUE TO
SLOWLY RECEDE AS OF WEDNESDAY AFTERNOON. ADDITIONAL MINOR REDUCTIONS
IN RIVER LEVELS WILL CONTINUE THROUGH THE NEXT 24 TO 48 HOURS BEFORE
HOLDING STEADY THROUGH THE WEEKEND. RECENT RAINFALL IN THE UPSTREAM
SOUTH PLATTE RIVER BASIN WILL BRING ADDITIONAL RIVER LEVEL RISES FOR
THE FIRST HALF OF NEXT WEEK...HOWEVER THE CRESTS SHOULD NOT BE
HIGHER THAN WHAT WAS EXPERIENCED LAST WEEKEND AND EARLIER THIS WEEK.

MORE SHOWERS AND THUNDERSTORMS ARE FORECAST WITHIN THE RIVER BASIN
LATER THIS WEEK. WHILE THE RAINFALL IS NOT EXPECTED TO RESULT IN
IMMEDIATE RISES ALONG THE RIVER...IT MAY BE A CONCERN FOR LOCAL
FLOOD MITIGATION EFFORTS DUE TO LOCALLY HEAVY RAINFALL RATES. THE
ADDITIONAL RAINFALL AND SNOW MELT RUNOFF FROM THE COLORADO FRONT
RANGE WILL KEEP ELEVATED FLOWS ON THE SOUTH PLATTE AND PLATTE RIVERS
IN SOUTHWEST NEBRASKA THROUGH THE END OF THE MONTH.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM CDT /7 AM MDT/ THIS MORNING FOR NEZ004-
005-022>025-035>037-094.

&&

$$

SHORT TERM...MARTIN
LONG TERM...CDC
AVIATION...POWER
HYDROLOGY...MARTIN








    US Dept of Commerce
    National Oceanic and Atmospheric Administration
    National Weather Service
    1325 East West Highway
    Silver Spring, MD 20910
    Page Author: NWS Internet Services Team
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities