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000
FXUS65 KTWC 201555 RRA
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
855 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...CLEAR TO PARTLY CLOUDY SKIES ACROSS SOUTHEAST ARIZONA
THIS MORNING UNDER DRY WEST TO NORTHWESTERLY FLOW ALOFT. 12Z KTWC
SOUNDING DEPICTS A RELATIVELY STEEP INVERSION WHICH WILL MIX OUT AS
THE DAY PROGRESSES TO ABOUT 850MB. EXPECT HIGH TEMPERATURES A FEW
DEGREES WARMER THAN YESTERDAY...TOPPING OUT IN THE LOWER 60S IN THE
TUCSON AREA.

AS A LARGE RIDGE OF HIGH PRESSURE SETS UP ACROSS THE EASTERN
PACIFIC...SOUTHEAST ARIZONA WILL BE ON THE EASTERN SIDE OF THE RIDGE
WITH NORTHWESTERLY FLOW ALOFT AND GRADUALLY RISING HEIGHTS SUNDAY
AND MONDAY. THIS WILL BRING A SLIGHT UPTICK IN DAYTIME
TEMPERATURES SUNDAY AND MONDAY AS HIGHS WILL BE NEAR NORMAL SUNDAY
AND ABOUT 5 DEGREES ABOVE NORMAL MONDAY. THERE WILL BE SOME MAINLY
THIN CIRROFORM CLOUDINESS MOVING THROUGH FROM TIME TO TIME ON THE
NORTHWESTERLY FLOW ALOFT.

TROUGHINESS WILL DEEPEN MAINLY ACROSS THE PLAINS TUESDAY INTO
WEDNESDAY. EXPECT HIGH PRESSURE TO STRENGTHEN ACROSS THE SOUTHERN
ROCKIES WITH A WEAK COLD FRONT FROM THE NORTH MOVING THROUGH
SOUTHEAST ARIZONA MONDAY NIGHT. CAN`T RULE OUT JUST ENOUGH MOISTURE
TO SQUEEZE OUT A FLURRY OR TWO IN THE WHITE MOUNTAINS MONDAY NIGHT
BUT WILL LEAVE FORECAST DRY AT THIS TIME. TEMPERATURES WILL DROP
BACK JUST A COUPLE OF DEGREES MAINLY FOR GRAHAM/GREENLEE/COCHISE
TUESDAY WITH LITTLE NOTICEABLE CHANGE FROM TUCSON WESTWARD OTHER
THAN THE WIND SHIFT.

THE NEXT SYSTEM IS PROGGED TO MOVE INTO THE WESTERN US BY THURSDAY
AND FRIDAY. LATEST TRENDS FAVOR A SOLUTION CLOSE TO THE 00Z ECMWF
AND ENSEMBLE MEANS WHICH WILL KEEP THE BULK OF THE MOISTURE TO THE
NORTH OF OUR AREA AND SOME GUSTY WINDS DUE TO A TIGHTER PRESSURE
GRADIENT. WILL KEEP SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
REEVALUATE WITH THE 12Z MODEL SUITE.

&&

.AVIATION...VALID THRU 21/18Z.
SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU THIS AFTERNOON. SURFACE WIND
LESS THAN 10 KTS WILL PREVAIL THROUGH THE PERIOD. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

GL







000
FXUS65 KTWC 201555 RRA
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
855 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...CLEAR TO PARTLY CLOUDY SKIES ACROSS SOUTHEAST ARIZONA
THIS MORNING UNDER DRY WEST TO NORTHWESTERLY FLOW ALOFT. 12Z KTWC
SOUNDING DEPICTS A RELATIVELY STEEP INVERSION WHICH WILL MIX OUT AS
THE DAY PROGRESSES TO ABOUT 850MB. EXPECT HIGH TEMPERATURES A FEW
DEGREES WARMER THAN YESTERDAY...TOPPING OUT IN THE LOWER 60S IN THE
TUCSON AREA.

AS A LARGE RIDGE OF HIGH PRESSURE SETS UP ACROSS THE EASTERN
PACIFIC...SOUTHEAST ARIZONA WILL BE ON THE EASTERN SIDE OF THE RIDGE
WITH NORTHWESTERLY FLOW ALOFT AND GRADUALLY RISING HEIGHTS SUNDAY
AND MONDAY. THIS WILL BRING A SLIGHT UPTICK IN DAYTIME
TEMPERATURES SUNDAY AND MONDAY AS HIGHS WILL BE NEAR NORMAL SUNDAY
AND ABOUT 5 DEGREES ABOVE NORMAL MONDAY. THERE WILL BE SOME MAINLY
THIN CIRROFORM CLOUDINESS MOVING THROUGH FROM TIME TO TIME ON THE
NORTHWESTERLY FLOW ALOFT.

TROUGHINESS WILL DEEPEN MAINLY ACROSS THE PLAINS TUESDAY INTO
WEDNESDAY. EXPECT HIGH PRESSURE TO STRENGTHEN ACROSS THE SOUTHERN
ROCKIES WITH A WEAK COLD FRONT FROM THE NORTH MOVING THROUGH
SOUTHEAST ARIZONA MONDAY NIGHT. CAN`T RULE OUT JUST ENOUGH MOISTURE
TO SQUEEZE OUT A FLURRY OR TWO IN THE WHITE MOUNTAINS MONDAY NIGHT
BUT WILL LEAVE FORECAST DRY AT THIS TIME. TEMPERATURES WILL DROP
BACK JUST A COUPLE OF DEGREES MAINLY FOR GRAHAM/GREENLEE/COCHISE
TUESDAY WITH LITTLE NOTICEABLE CHANGE FROM TUCSON WESTWARD OTHER
THAN THE WIND SHIFT.

THE NEXT SYSTEM IS PROGGED TO MOVE INTO THE WESTERN US BY THURSDAY
AND FRIDAY. LATEST TRENDS FAVOR A SOLUTION CLOSE TO THE 00Z ECMWF
AND ENSEMBLE MEANS WHICH WILL KEEP THE BULK OF THE MOISTURE TO THE
NORTH OF OUR AREA AND SOME GUSTY WINDS DUE TO A TIGHTER PRESSURE
GRADIENT. WILL KEEP SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
REEVALUATE WITH THE 12Z MODEL SUITE.

&&

.AVIATION...VALID THRU 21/18Z.
SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU THIS AFTERNOON. SURFACE WIND
LESS THAN 10 KTS WILL PREVAIL THROUGH THE PERIOD. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

GL






000
FXUS65 KTWC 200923 RRA
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
225 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...TWO AREAS OF CONCERN FOR THIS FORECAST PERIOD...ONE
VERY SHORT TERM AND THE OTHER LONG TERM.  THE SHORT TERM CONCERN
RELATES TO THE POTENTIAL FOR FOG DEVELOPMENT EARLY THIS MORNING.  AT
THIS TIME A LARGE PORTION OF THE FORECAST AREA EAST OF TUCSON HAS
TEMP/DEWPOINTS WITHIN 3 DEGREES WITH A FEW LOCATIONS NEAR THE NEW
MEXICO BORDER WITH A ZERO SPREAD.  THUS FAR NO FOG IS INDICATED IN
ANY OBS OR SATELLITE PIX AND NOW HAVE A BAND OF RELATIVELY THICK
CIRRUS CLOUDS MOVING ACROSS THE AREA WHICH SHOULD HINDER FOG
DEVELOPMENT.  SO HAVE TWEAKED THE WORDING FROM AREAS OF FOG/FREEZING
FOG TO PATCHY.  WHATEVER FORMS WILL BURN OFF QUICKER THAN
YESTERDAY.  OTHERWISE IT WILL BE A COUPLE OF DEGREES WARMER THIS
AFTERNOON WITH CONTINUED LIGHT WINDS AND A FEW HIGH CLOUDS PASSING
BY AT TIMES.

THEN SUNDAY THROUGH WEDNESDAY THE AREA WILL HAVE A DRY NORTHWEST
FLOW OVERHEAD WITH TEMPERATURES WARMING TO A FEW DEGREES WARMER THAN
NORMAL OVERALL.  THE ONLY ITEM OF INTEREST THROUGH THIS PERIOD IS A
PASSING SHORTWAVE MONDAY NIGHT WHICH WILL TRIM TEMPERATURES BACK A
FEW DEGREES TUESDAY AFTERNOON AND NIGHT.  AT THIS POINT STILL
CARRYING A DRY FORECAST ALTHOUGH THERE COULD BE A FEW
FLURRIES/SPRINKLES ACROSS THE WHITE MOUNTAINS MONDAY NIGHT AS THE
AXIS OF THIS SYSTEM PASSES.

NOW FOR THE SECOND PERIOD OF CONCERN...CHRISTMAS DAY AND FRIDAY.  A
TROUGH IS EXPECTED TO IMPACT THE WEST COAST WEDNESDAY THEN MOVE
SOUTHEAST ACROSS THE REGION THURSDAY INTO FRIDAY.  THE BIG QUESTION
HAS BEEN THE DEPTH OF THE SYSTEM AS IT PASSES.  THIS EVENINGS 00Z
GFS OPERATIONAL RUN IS VERY FLAT WITH THIS FEATURE WITH BASICALLY NO
IMPACT ON THE AREA.  HOWEVER...LOOKING AT A PLOT OF THE 00Z GFS
ENSEMBLE MEMBERS SHOWS THIS SOLUTION TO BE ONE OF THE 5 WARM RUNS
WHILE THE OTHER 15 RUNS MORE CLOSELY RESEMBLE THE 00Z HIGH RES GFS
AND THE 00Z ECMWF WHICH IS SIMILAR TO THE PREVIOUS COUPLE OF ECMWF
RUNS...BEING A DEEPER AND SHARPER TROUGH.

THEREFORE HAVE TOSSED THE 00Z GFS AND LEANED ON THE HIGH RES GFS
WHICH IS SIMILAR TO BUT A BIT WEAKER THAN THE ECMWF.  WHAT THAT
MEANS IS A CHANCE OF A FEW SNOW/RAIN SHOWERS ACROSS THE WHITE
MOUNTAINS AND THE NE SKY ISLANDS CHRISTMAS DAY INTO FRIDAY WITH A
GOOD NORTHWEST BREEZE BOTH DAYS WITH TEMPERATURES COOLING BACK
DOWN TO OR BELOW NORMAL CHRISTMAS DAY INTO SATURDAY.  CERNIGLIA

&&

.AVIATION...VALID THRU 21/12Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER THROUGH AROUND 20/17Z. SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU
THIS AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH
THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 200923 RRA
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
225 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...TWO AREAS OF CONCERN FOR THIS FORECAST PERIOD...ONE
VERY SHORT TERM AND THE OTHER LONG TERM.  THE SHORT TERM CONCERN
RELATES TO THE POTENTIAL FOR FOG DEVELOPMENT EARLY THIS MORNING.  AT
THIS TIME A LARGE PORTION OF THE FORECAST AREA EAST OF TUCSON HAS
TEMP/DEWPOINTS WITHIN 3 DEGREES WITH A FEW LOCATIONS NEAR THE NEW
MEXICO BORDER WITH A ZERO SPREAD.  THUS FAR NO FOG IS INDICATED IN
ANY OBS OR SATELLITE PIX AND NOW HAVE A BAND OF RELATIVELY THICK
CIRRUS CLOUDS MOVING ACROSS THE AREA WHICH SHOULD HINDER FOG
DEVELOPMENT.  SO HAVE TWEAKED THE WORDING FROM AREAS OF FOG/FREEZING
FOG TO PATCHY.  WHATEVER FORMS WILL BURN OFF QUICKER THAN
YESTERDAY.  OTHERWISE IT WILL BE A COUPLE OF DEGREES WARMER THIS
AFTERNOON WITH CONTINUED LIGHT WINDS AND A FEW HIGH CLOUDS PASSING
BY AT TIMES.

THEN SUNDAY THROUGH WEDNESDAY THE AREA WILL HAVE A DRY NORTHWEST
FLOW OVERHEAD WITH TEMPERATURES WARMING TO A FEW DEGREES WARMER THAN
NORMAL OVERALL.  THE ONLY ITEM OF INTEREST THROUGH THIS PERIOD IS A
PASSING SHORTWAVE MONDAY NIGHT WHICH WILL TRIM TEMPERATURES BACK A
FEW DEGREES TUESDAY AFTERNOON AND NIGHT.  AT THIS POINT STILL
CARRYING A DRY FORECAST ALTHOUGH THERE COULD BE A FEW
FLURRIES/SPRINKLES ACROSS THE WHITE MOUNTAINS MONDAY NIGHT AS THE
AXIS OF THIS SYSTEM PASSES.

NOW FOR THE SECOND PERIOD OF CONCERN...CHRISTMAS DAY AND FRIDAY.  A
TROUGH IS EXPECTED TO IMPACT THE WEST COAST WEDNESDAY THEN MOVE
SOUTHEAST ACROSS THE REGION THURSDAY INTO FRIDAY.  THE BIG QUESTION
HAS BEEN THE DEPTH OF THE SYSTEM AS IT PASSES.  THIS EVENINGS 00Z
GFS OPERATIONAL RUN IS VERY FLAT WITH THIS FEATURE WITH BASICALLY NO
IMPACT ON THE AREA.  HOWEVER...LOOKING AT A PLOT OF THE 00Z GFS
ENSEMBLE MEMBERS SHOWS THIS SOLUTION TO BE ONE OF THE 5 WARM RUNS
WHILE THE OTHER 15 RUNS MORE CLOSELY RESEMBLE THE 00Z HIGH RES GFS
AND THE 00Z ECMWF WHICH IS SIMILAR TO THE PREVIOUS COUPLE OF ECMWF
RUNS...BEING A DEEPER AND SHARPER TROUGH.

THEREFORE HAVE TOSSED THE 00Z GFS AND LEANED ON THE HIGH RES GFS
WHICH IS SIMILAR TO BUT A BIT WEAKER THAN THE ECMWF.  WHAT THAT
MEANS IS A CHANCE OF A FEW SNOW/RAIN SHOWERS ACROSS THE WHITE
MOUNTAINS AND THE NE SKY ISLANDS CHRISTMAS DAY INTO FRIDAY WITH A
GOOD NORTHWEST BREEZE BOTH DAYS WITH TEMPERATURES COOLING BACK
DOWN TO OR BELOW NORMAL CHRISTMAS DAY INTO SATURDAY.  CERNIGLIA

&&

.AVIATION...VALID THRU 21/12Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER THROUGH AROUND 20/17Z. SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU
THIS AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH
THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 200923
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...TWO AREAS OF CONCERN FOR THIS FORECAST PERIOD...ONE
VERY SHORT TERM AND THE OTHER LONG TERM.  THE SHORT TERM CONCERN
RELATES TO THE POTENTIAL FOR FOG DEVELOPMENT EARLY THIS MORNING.  AT
THIS TIME A LARGE PORTION OF THE FORECAST AREA EAST OF TUCSON HAS
TEMP/DEWPOINTS WITHIN 3 DEGREES WITH A FEW LOCATIONS NEAR THE NEW
MEXICO BORDER WITH A ZERO SPREAD.  THUS FAR NO FOG IS INDICATED IN
ANY OBS OR SATELLITE PIX AND NOW HAVE A BAND OF RELATIVELY THICK
CIRRUS CLOUDS MOVING ACROSS THE AREA WHICH SHOULD HINDER FOG
DEVELOPMENT.  SO HAVE TWEAKED THE WORDING FROM AREAS OF FOG/FREEZING
FOG TO PATCHY.  WHATEVER FORMS WILL BURN OFF QUICKER THAN
YESTERDAY.  OTHERWISE IT WILL BE A COUPLE OF DEGREES WARMER THIS
AFTERNOON WITH CONTINUED LIGHT WINDS AND A FEW HIGH CLOUDS PASSING
BY AT TIMES.

THEN SUNDAY THROUGH WEDNESDAY THE AREA WILL HAVE A DRY NORTHWEST
FLOW OVERHEAD WITH TEMPERATURES WARMING TO A FEW DEGREES WARMER THAN
NORMAL OVERALL.  THE ONLY ITEM OF INTEREST THROUGH THIS PERIOD IS A
PASSING SHORTWAVE MONDAY NIGHT WHICH WILL TRIM TEMPERATURES BACK A
FEW DEGREES TUESDAY AFTERNOON AND NIGHT.  AT THIS POINT STILL
CARRYING A DRY FORECAST ALTHOUGH THERE COULD BE A FEW
FLURRIES/SPRINKLES ACROSS THE WHITE MOUNTAINS MONDAY NIGHT AS THE
AXIS OF THIS SYSTEM PASSES.

NOW FOR THE SECOND PERIOD OF CONCERN...CHRISTMAS DAY AND FRIDAY.  A
TROUGH IS EXPECTED TO IMPACT THE WEST COAST WEDNESDAY THEN MOVE
SOUTHEAST ACROSS THE REGION THURSDAY INTO FRIDAY.  THE BIG QUESTION
HAS BEEN THE DEPTH OF THE SYSTEM AS IT PASSES.  THIS EVENINGS 00Z
GFS OPERATIONAL RUN IS VERY FLAT WITH THIS FEATURE WITH BASICALLY NO
IMPACT ON THE AREA.  HOWEVER...LOOKING AT A PLOT OF THE 00Z GFS
ENSEMBLE MEMBERS SHOWS THIS SOLUTION TO BE ONE OF THE 5 WARM RUNS
WHILE THE OTHER 15 RUNS MORE CLOSELY RESEMBLE THE 00Z HIGH RES GFS
AND THE 00Z ECMWF WHICH IS SIMILAR TO THE PREVIOUS COUPLE OF ECMWF
RUNS...BEING A DEEPER AND SHARPER TROUGH.

THEREFORE HAVE TOSSED THE 00Z GFS AND LEANED ON THE HIGH RES GFS
WHICH IS SIMILAR TO BUT A BIT WEAKER THAN THE ECMWF.  WHAT THAT
MEANS IS A CHANCE OF A FEW SNOW/RAIN SHOWERS ACROSS THE WHITE
MOUNTAINS AND THE NE SKY ISLANDS CHRISTMAS DAY INTO FRIDAY WITH A
GOOD NORTHWEST BREEZE BOTH DAYS WITH TEMPERATURES COOLING BACK
DOWN TO OR BELOW NORMAL CHRISTMAS DAY INTO SATURDAY.  CERNIGLIA

&&

.AVIATION...VALID THRU 21/12Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER THROUGH AROUND 20/17Z. SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU
THIS AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH
THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 200923
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST SAT DEC 20 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES
THIS WEEKEND.  A FEW PATCHES OF FOG AND FREEZING FOG ARE EXPECTED
AGAIN EARLY THIS MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND
GRAHAM COUNTY.  FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE
TO ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE.
UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...TWO AREAS OF CONCERN FOR THIS FORECAST PERIOD...ONE
VERY SHORT TERM AND THE OTHER LONG TERM.  THE SHORT TERM CONCERN
RELATES TO THE POTENTIAL FOR FOG DEVELOPMENT EARLY THIS MORNING.  AT
THIS TIME A LARGE PORTION OF THE FORECAST AREA EAST OF TUCSON HAS
TEMP/DEWPOINTS WITHIN 3 DEGREES WITH A FEW LOCATIONS NEAR THE NEW
MEXICO BORDER WITH A ZERO SPREAD.  THUS FAR NO FOG IS INDICATED IN
ANY OBS OR SATELLITE PIX AND NOW HAVE A BAND OF RELATIVELY THICK
CIRRUS CLOUDS MOVING ACROSS THE AREA WHICH SHOULD HINDER FOG
DEVELOPMENT.  SO HAVE TWEAKED THE WORDING FROM AREAS OF FOG/FREEZING
FOG TO PATCHY.  WHATEVER FORMS WILL BURN OFF QUICKER THAN
YESTERDAY.  OTHERWISE IT WILL BE A COUPLE OF DEGREES WARMER THIS
AFTERNOON WITH CONTINUED LIGHT WINDS AND A FEW HIGH CLOUDS PASSING
BY AT TIMES.

THEN SUNDAY THROUGH WEDNESDAY THE AREA WILL HAVE A DRY NORTHWEST
FLOW OVERHEAD WITH TEMPERATURES WARMING TO A FEW DEGREES WARMER THAN
NORMAL OVERALL.  THE ONLY ITEM OF INTEREST THROUGH THIS PERIOD IS A
PASSING SHORTWAVE MONDAY NIGHT WHICH WILL TRIM TEMPERATURES BACK A
FEW DEGREES TUESDAY AFTERNOON AND NIGHT.  AT THIS POINT STILL
CARRYING A DRY FORECAST ALTHOUGH THERE COULD BE A FEW
FLURRIES/SPRINKLES ACROSS THE WHITE MOUNTAINS MONDAY NIGHT AS THE
AXIS OF THIS SYSTEM PASSES.

NOW FOR THE SECOND PERIOD OF CONCERN...CHRISTMAS DAY AND FRIDAY.  A
TROUGH IS EXPECTED TO IMPACT THE WEST COAST WEDNESDAY THEN MOVE
SOUTHEAST ACROSS THE REGION THURSDAY INTO FRIDAY.  THE BIG QUESTION
HAS BEEN THE DEPTH OF THE SYSTEM AS IT PASSES.  THIS EVENINGS 00Z
GFS OPERATIONAL RUN IS VERY FLAT WITH THIS FEATURE WITH BASICALLY NO
IMPACT ON THE AREA.  HOWEVER...LOOKING AT A PLOT OF THE 00Z GFS
ENSEMBLE MEMBERS SHOWS THIS SOLUTION TO BE ONE OF THE 5 WARM RUNS
WHILE THE OTHER 15 RUNS MORE CLOSELY RESEMBLE THE 00Z HIGH RES GFS
AND THE 00Z ECMWF WHICH IS SIMILAR TO THE PREVIOUS COUPLE OF ECMWF
RUNS...BEING A DEEPER AND SHARPER TROUGH.

THEREFORE HAVE TOSSED THE 00Z GFS AND LEANED ON THE HIGH RES GFS
WHICH IS SIMILAR TO BUT A BIT WEAKER THAN THE ECMWF.  WHAT THAT
MEANS IS A CHANCE OF A FEW SNOW/RAIN SHOWERS ACROSS THE WHITE
MOUNTAINS AND THE NE SKY ISLANDS CHRISTMAS DAY INTO FRIDAY WITH A
GOOD NORTHWEST BREEZE BOTH DAYS WITH TEMPERATURES COOLING BACK
DOWN TO OR BELOW NORMAL CHRISTMAS DAY INTO SATURDAY.  CERNIGLIA

&&

.AVIATION...VALID THRU 21/12Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER THROUGH AROUND 20/17Z. SCT TO LCLY BKN MOSTLY HIGH CLOUDS THRU
THIS AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH
THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD...AS AN UPPER LEVEL DISTURBANCE MOVES NORTHWEST TO SOUTHEAST
ACROSS THE FOUR CORNERS REGION. AT THIS TIME CONFIDENCE IS LOW
CONCERNING THE TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER
MAKER WHICH MAY AFFECT THE REGION LATE NEXT WEEK. A SLIGHT CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE...ALONG WITH AN
INCREASE IN WINDS ON THURSDAY...MAINLY FOR AREAS SOUTH AND EAST OF
TUCSON TOWARD THE INTERNATIONAL BORDER AS WELL AS THE BORDER WITH
NEW MEXICO.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 200437
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
935 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW TEMPERATURES THIS
WEEKEND. SOME AREAS OF FOG AND FREEZING FOG ARE EXPECTED AGAIN EARLY
SATURDAY MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND GRAHAM
COUNTY.   FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE TO
ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE. UNSETTLED
AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...MAIN FORECAST CONCERN TONIGHT IS DEVELOPMENT OF FOG
AGAIN MAINLY E OF TUCSON. COULD SEE AREAS OF DENSE FOG AGAIN BUT AT
THIS TIME DON`T BELIEVE THAT IT WILL BE WIDESPREAD ENOUGH FOR AN
ADVISORY BUT OBS WILL BE MONITORED CLOSELY OVERNIGHT INTO SATURDAY
MORNING. OTHERWISE SATELLITE IMAGERY SHOWED HIGH CLOUDS OVER WRN AZ
MOVING E. PARTLY CLOUDY FORECAST FOR TONIGHT RIGHT ON TRACK. CLOUDS
MAY TAKE AN EDGE OFF LOW TEMPERATURES BUT OVERALL IT WILL STILL BE
CHILLY TO COLD WITH AREAS OF FROST. CHECK PREVIOUS DISCUSSION BELOW
FOR ADDITIONAL FORECAST DETAILS FOR THE WEEKEND INTO NEXT WEEK.

&&

.AVIATION...VALID THRU 21/00Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER 20/09Z THROUGH 20/17Z. SCT TO LCLY BKN HIGH CLOUDS THRU
SATURDAY AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL
THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE TIMING AND
IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY AFFECT THE
REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR VALLEY
RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.PREVIOUS DISCUSSION...
IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT IS CENTERED JUST
WEST OF US AT THIS TIME WITH SOME THIN CIRROFORM CLOUDS ACROSS
WESTERN ARIZONA AND MORE EXTENSIVE MID AND HIGH LEVEL CLOUDS ACROSS
THE EASTERN PACIFIC PUSHING INTO SOUTHERN CALIFORNIA. CONSIDERING
AMPLE LOW LEVEL MOISTURE REMAINS TONIGHT WE THINK THERE WILL BE SOME
AREAS OF FOG AND FREEZING FOG AGAIN EARLY SATURDAY MORNING ACROSS
THE VALLEYS OF GRAHAM AND COCHISE COUNTY. THE UPPER GILA RIVER
VALLEY WILL AGAIN HAVE THE BEST CHANCE OF SEEING FOG AND FREEZING
FOG. SOME AREAS OF FROST WILL BE POSSIBLE AS WELL FOR SOME OF THE
OUTLYING AREAS OF THE TUCSON METRO. THERE WILL BE SOME THIN
CIRROFORM CLOUDS OVERNIGHT WHICH COULD HELP MITIGATE LOW
TEMPERATURES AND FOG SLIGHTLY BUT CONFIDENCE IS HIGH ENOUGH TO PUT
AREAS OF FOG IN THE FORECAST FOR THE VALLEYS EAST OF TUCSON.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK AS RIDGING ALOFT IS CENTERED ACROSS
THE EASTERN PACIFIC AND TROUGHINESS IS LOCATED OVER THE PLAINS.
TEMPERATURES WILL BE NEAR NORMAL SUNDAY AND ABOUT 5 DEGREES ABOVE
NORMAL MONDAY. THERE WILL BE A WEAK COLD FRONT MOVING THROUGH FROM
THE NORTH-NORTHEAST EARLY TUESDAY BUT THIS WILL HAVE LITTLE IMPACT
ON TEMPERATURES FROM TUCSON WESTWARD WITH PERHAPS SLIGHT COOLING FOR
EASTERN AREAS TUESDAY INTO WEDNESDAY.

BY LATE NEXT WEEK...THERE REMAINS CONSIDERABLE DIFFERENCES IN THE
GLOBAL MODEL GUIDANCE AS ANOTHER TROUGH MOVES INTO THE WESTERN US.
THE 12Z GFS KEEPS MAINLY ZONAL WESTERLY FLOW THIS FAR SOUTH WITH THE
12Z CANADIAN AND ECMWF MORE AMPLIFIED WITH THE TROUGH LATE NEXT
WEEK. WILL TAKE A MIDDLE OF THE ROAD APPROACH CLOSE TO 12Z GEFS AND
ECMWF ENSEMBLE MEANS. THUS...HAVE ONLY MADE MINOR TWEAKS TO THE
ONGOING FORECAST WITH SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
ESPECIALLY IN THE WHITE MOUNTAINS THURSDAY AND FRIDAY. TEMPERATURES
WILL DROP BACK DOWN TO NEAR NORMAL VALUES LATE NEXT WEEK.


.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 200437
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
935 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW TEMPERATURES THIS
WEEKEND. SOME AREAS OF FOG AND FREEZING FOG ARE EXPECTED AGAIN EARLY
SATURDAY MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND GRAHAM
COUNTY.   FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE TO
ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE. UNSETTLED
AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...MAIN FORECAST CONCERN TONIGHT IS DEVELOPMENT OF FOG
AGAIN MAINLY E OF TUCSON. COULD SEE AREAS OF DENSE FOG AGAIN BUT AT
THIS TIME DON`T BELIEVE THAT IT WILL BE WIDESPREAD ENOUGH FOR AN
ADVISORY BUT OBS WILL BE MONITORED CLOSELY OVERNIGHT INTO SATURDAY
MORNING. OTHERWISE SATELLITE IMAGERY SHOWED HIGH CLOUDS OVER WRN AZ
MOVING E. PARTLY CLOUDY FORECAST FOR TONIGHT RIGHT ON TRACK. CLOUDS
MAY TAKE AN EDGE OFF LOW TEMPERATURES BUT OVERALL IT WILL STILL BE
CHILLY TO COLD WITH AREAS OF FROST. CHECK PREVIOUS DISCUSSION BELOW
FOR ADDITIONAL FORECAST DETAILS FOR THE WEEKEND INTO NEXT WEEK.

&&

.AVIATION...VALID THRU 21/00Z.
EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR FREEZING FOG
AFTER 20/09Z THROUGH 20/17Z. SCT TO LCLY BKN HIGH CLOUDS THRU
SATURDAY AFTERNOON. SURFACE WIND LESS THAN 10 KTS WILL PREVAIL
THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE TIMING AND
IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY AFFECT THE
REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR VALLEY
RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.PREVIOUS DISCUSSION...
IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT IS CENTERED JUST
WEST OF US AT THIS TIME WITH SOME THIN CIRROFORM CLOUDS ACROSS
WESTERN ARIZONA AND MORE EXTENSIVE MID AND HIGH LEVEL CLOUDS ACROSS
THE EASTERN PACIFIC PUSHING INTO SOUTHERN CALIFORNIA. CONSIDERING
AMPLE LOW LEVEL MOISTURE REMAINS TONIGHT WE THINK THERE WILL BE SOME
AREAS OF FOG AND FREEZING FOG AGAIN EARLY SATURDAY MORNING ACROSS
THE VALLEYS OF GRAHAM AND COCHISE COUNTY. THE UPPER GILA RIVER
VALLEY WILL AGAIN HAVE THE BEST CHANCE OF SEEING FOG AND FREEZING
FOG. SOME AREAS OF FROST WILL BE POSSIBLE AS WELL FOR SOME OF THE
OUTLYING AREAS OF THE TUCSON METRO. THERE WILL BE SOME THIN
CIRROFORM CLOUDS OVERNIGHT WHICH COULD HELP MITIGATE LOW
TEMPERATURES AND FOG SLIGHTLY BUT CONFIDENCE IS HIGH ENOUGH TO PUT
AREAS OF FOG IN THE FORECAST FOR THE VALLEYS EAST OF TUCSON.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK AS RIDGING ALOFT IS CENTERED ACROSS
THE EASTERN PACIFIC AND TROUGHINESS IS LOCATED OVER THE PLAINS.
TEMPERATURES WILL BE NEAR NORMAL SUNDAY AND ABOUT 5 DEGREES ABOVE
NORMAL MONDAY. THERE WILL BE A WEAK COLD FRONT MOVING THROUGH FROM
THE NORTH-NORTHEAST EARLY TUESDAY BUT THIS WILL HAVE LITTLE IMPACT
ON TEMPERATURES FROM TUCSON WESTWARD WITH PERHAPS SLIGHT COOLING FOR
EASTERN AREAS TUESDAY INTO WEDNESDAY.

BY LATE NEXT WEEK...THERE REMAINS CONSIDERABLE DIFFERENCES IN THE
GLOBAL MODEL GUIDANCE AS ANOTHER TROUGH MOVES INTO THE WESTERN US.
THE 12Z GFS KEEPS MAINLY ZONAL WESTERLY FLOW THIS FAR SOUTH WITH THE
12Z CANADIAN AND ECMWF MORE AMPLIFIED WITH THE TROUGH LATE NEXT
WEEK. WILL TAKE A MIDDLE OF THE ROAD APPROACH CLOSE TO 12Z GEFS AND
ECMWF ENSEMBLE MEANS. THUS...HAVE ONLY MADE MINOR TWEAKS TO THE
ONGOING FORECAST WITH SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
ESPECIALLY IN THE WHITE MOUNTAINS THURSDAY AND FRIDAY. TEMPERATURES
WILL DROP BACK DOWN TO NEAR NORMAL VALUES LATE NEXT WEEK.


.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 192134
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
234 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW TEMPERATURES THIS
WEEKEND. SOME AREAS OF FOG AND FREEZING FOG ARE EXPECTED AGAIN EARLY
SATURDAY MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND GRAHAM
COUNTY.   FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE TO
ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE. UNSETTLED
AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...SKIES ARE NOW MOSTLY SUNNY THIS AFTERNOON ACROSS
SOUTHEAST ARIZONA WITH BELOW NORMAL TEMPERATURES. A STEEP INVERSION
THIS MORNING WITH EXTENSIVE AREAS OF CLOUDS AND FOG IN THE VALLEYS
FROM TUCSON SOUTH AND EASTWARD HAVE FINALLY DISSIPATED WITH THE LAST
VESTIGES OF CLOUDS CLEARING AROUND 1 PM NEAR SAFFORD. IN THE LARGER
SCALE...WEAK SHORTWAVE RIDGING ALOFT IS CENTERED JUST WEST OF US AT
THIS TIME WITH SOME THIN CIRROFORM CLOUDS ACROSS WESTERN ARIZONA AND
MORE EXTENSIVE MID AND HIGH LEVEL CLOUDS ACROSS THE EASTERN PACIFIC
PUSHING INTO SOUTHERN CALIFORNIA. CONSIDERING AMPLE LOW LEVEL
MOISTURE REMAINS TONIGHT WE THINK THERE WILL BE SOME AREAS OF FOG
AND FREEZING FOG AGAIN EARLY SATURDAY MORNING ACROSS THE VALLEYS OF
GRAHAM AND COCHISE COUNTY. THE UPPER GILA RIVER VALLEY WILL AGAIN
HAVE THE BEST CHANCE OF SEEING FOG AND FREEZING FOG. SOME AREAS OF
FROST WILL BE POSSIBLE AS WELL FOR SOME OF THE OUTLYING AREAS OF THE
TUCSON METRO. THERE WILL BE SOME THIN CIRROFORM CLOUDS OVERNIGHT
WHICH COULD HELP MITIGATE LOW TEMPERATURES AND FOG SLIGHTLY BUT
CONFIDENCE IS HIGH ENOUGH TO PUT AREAS OF FOG IN THE FORECAST FOR
THE VALLEYS EAST OF TUCSON.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK AS RIDGING ALOFT IS CENTERED ACROSS
THE EASTERN PACIFIC AND TROUGHINESS IS LOCATED OVER THE PLAINS.
TEMPERATURES WILL BE NEAR NORMAL SUNDAY AND ABOUT 5 DEGREES ABOVE
NORMAL MONDAY. THERE WILL BE A WEAK COLD FRONT MOVING THROUGH FROM
THE NORTH-NORTHEAST EARLY TUESDAY BUT THIS WILL HAVE LITTLE IMPACT
ON TEMPERATURES FROM TUCSON WESTWARD WITH PERHAPS SLIGHT COOLING FOR
EASTERN AREAS TUESDAY INTO WEDNESDAY.

BY LATE NEXT WEEK...THERE REMAINS CONSIDERABLE DIFFERENCES IN THE
GLOBAL MODEL GUIDANCE AS ANOTHER TROUGH MOVES INTO THE WESTERN US.
THE 12Z GFS KEEPS MAINLY ZONAL WESTERLY FLOW THIS FAR SOUTH WITH THE
12Z CANADIAN AND ECMWF MORE AMPLIFIED WITH THE TROUGH LATE NEXT
WEEK. WILL TAKE A MIDDLE OF THE ROAD APPROACH CLOSE TO 12Z GEFS AND
ECMWF ENSEMBLE MEANS. THUS...HAVE ONLY MADE MINOR TWEAKS TO THE
ONGOING FORECAST WITH SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
ESPECIALLY IN THE WHITE MOUNTAINS THURSDAY AND FRIDAY. TEMPERATURES
WILL DROP BACK DOWN TO NEAR NORMAL VALUES LATE NEXT WEEK.


&&

.AVIATION...VALID THRU 21/00Z.
GENERALLY SKC WITH PERIODS OF SCT HIGH CLOUDS MOVING THROUGH EARLY
TONIGHT. EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR
FREEZING FOG AFTER 20/09Z THROUGH 20/17Z. OTHERWISE CLEAR SKIES AND
SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH THE PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE TIMING AND
IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY AFFECT THE
REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR VALLEY
RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...RH












000
FXUS65 KTWC 192134
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
234 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND NEAR TO SLIGHTLY BELOW TEMPERATURES THIS
WEEKEND. SOME AREAS OF FOG AND FREEZING FOG ARE EXPECTED AGAIN EARLY
SATURDAY MORNING MAINLY ACROSS THE VALLEYS OF COCHISE AND GRAHAM
COUNTY.   FOR EARLY TO MID NEXT WEEK...TEMPERATURES WILL RISE TO
ABOVE NORMAL LEVELS DUE TO A PASSING UPPER LEVEL RIDGE. UNSETTLED
AND COOLER WEATHER LOOKS LIKELY FOR THE END OF NEXT WEEK.

&&

.DISCUSSION...SKIES ARE NOW MOSTLY SUNNY THIS AFTERNOON ACROSS
SOUTHEAST ARIZONA WITH BELOW NORMAL TEMPERATURES. A STEEP INVERSION
THIS MORNING WITH EXTENSIVE AREAS OF CLOUDS AND FOG IN THE VALLEYS
FROM TUCSON SOUTH AND EASTWARD HAVE FINALLY DISSIPATED WITH THE LAST
VESTIGES OF CLOUDS CLEARING AROUND 1 PM NEAR SAFFORD. IN THE LARGER
SCALE...WEAK SHORTWAVE RIDGING ALOFT IS CENTERED JUST WEST OF US AT
THIS TIME WITH SOME THIN CIRROFORM CLOUDS ACROSS WESTERN ARIZONA AND
MORE EXTENSIVE MID AND HIGH LEVEL CLOUDS ACROSS THE EASTERN PACIFIC
PUSHING INTO SOUTHERN CALIFORNIA. CONSIDERING AMPLE LOW LEVEL
MOISTURE REMAINS TONIGHT WE THINK THERE WILL BE SOME AREAS OF FOG
AND FREEZING FOG AGAIN EARLY SATURDAY MORNING ACROSS THE VALLEYS OF
GRAHAM AND COCHISE COUNTY. THE UPPER GILA RIVER VALLEY WILL AGAIN
HAVE THE BEST CHANCE OF SEEING FOG AND FREEZING FOG. SOME AREAS OF
FROST WILL BE POSSIBLE AS WELL FOR SOME OF THE OUTLYING AREAS OF THE
TUCSON METRO. THERE WILL BE SOME THIN CIRROFORM CLOUDS OVERNIGHT
WHICH COULD HELP MITIGATE LOW TEMPERATURES AND FOG SLIGHTLY BUT
CONFIDENCE IS HIGH ENOUGH TO PUT AREAS OF FOG IN THE FORECAST FOR
THE VALLEYS EAST OF TUCSON.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK AS RIDGING ALOFT IS CENTERED ACROSS
THE EASTERN PACIFIC AND TROUGHINESS IS LOCATED OVER THE PLAINS.
TEMPERATURES WILL BE NEAR NORMAL SUNDAY AND ABOUT 5 DEGREES ABOVE
NORMAL MONDAY. THERE WILL BE A WEAK COLD FRONT MOVING THROUGH FROM
THE NORTH-NORTHEAST EARLY TUESDAY BUT THIS WILL HAVE LITTLE IMPACT
ON TEMPERATURES FROM TUCSON WESTWARD WITH PERHAPS SLIGHT COOLING FOR
EASTERN AREAS TUESDAY INTO WEDNESDAY.

BY LATE NEXT WEEK...THERE REMAINS CONSIDERABLE DIFFERENCES IN THE
GLOBAL MODEL GUIDANCE AS ANOTHER TROUGH MOVES INTO THE WESTERN US.
THE 12Z GFS KEEPS MAINLY ZONAL WESTERLY FLOW THIS FAR SOUTH WITH THE
12Z CANADIAN AND ECMWF MORE AMPLIFIED WITH THE TROUGH LATE NEXT
WEEK. WILL TAKE A MIDDLE OF THE ROAD APPROACH CLOSE TO 12Z GEFS AND
ECMWF ENSEMBLE MEANS. THUS...HAVE ONLY MADE MINOR TWEAKS TO THE
ONGOING FORECAST WITH SLIGHT CHANCE POPS NORTHEAST OF TUCSON AND
ESPECIALLY IN THE WHITE MOUNTAINS THURSDAY AND FRIDAY. TEMPERATURES
WILL DROP BACK DOWN TO NEAR NORMAL VALUES LATE NEXT WEEK.


&&

.AVIATION...VALID THRU 21/00Z.
GENERALLY SKC WITH PERIODS OF SCT HIGH CLOUDS MOVING THROUGH EARLY
TONIGHT. EASTERN AREAS COULD SEE DEVELOPMENT OF PATCHY FOG OR
FREEZING FOG AFTER 20/09Z THROUGH 20/17Z. OTHERWISE CLEAR SKIES AND
SURFACE WIND LESS THAN 10 KTS WILL PREVAIL THROUGH THE PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH WEDNESDAY.
20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN THROUGH THE
MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES WILL OCCUR
MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY INCLUDING
SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE TIMING AND
IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY AFFECT THE
REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR VALLEY
RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...RH













000
FXUS65 KTWC 191924 AAA
AFDTWC

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE TUCSON AZ
1225 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.UPDATE...AVIATION SECTION UPDATE ONLY. SEE BELOW.

&&

.DISCUSSION...STILL SOME AREAS OF FOG AND FREEZING FOG SHOWING UP
CLEARLY ON VISIBLE SATELLITE THIS MORNING MAINLY IN THE RIVER
VALLEYS SUCH AS THE SANTA CRUZ...SAN PEDRO...UPPER GILA AND SAN
SIMON. SURFACE OBSERVATIONS AT NOGALES...SAFFORD AND DOUGLAS
INDICATE THAT VISIBILITIES ARE BOUNCING AROUND FROM ABOUT 1/4SM TO
2SM. AS SOLAR INSOLATION INCREASES...EXPECT FOG AND LOW CLOUDS TO
BURN OFF AS THE MORNING PROGRESSES WITH MAINLY CLEAR SKIES AREAWIDE
AFTER 11 AM.

IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT WILL MOVE INTO
ARIZONA TODAY. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS
ABOUT 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. THERE IS A
POSSIBILITY OF A FEW PATCHES OF FOG AGAIN TONIGHT/EARLY SATURDAY IN
THE MOST PRONE RIVER VALLEY LOCATIONS...BUT THIS MIGHT BE MITIGATED
BY SOME CIRROFORM CLOUDS.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WITH GRADUALLY RISING HEIGHTS AND
THICKNESS VALUES AS RIDGING ALOFT IS CENTERED ACROSS THE EASTERN
PACIFIC. THIS WILL RESULT IN A CONTINUED WARMING TEMPERATURE TREND.
BY LATE NEXT WEEK...TROUGHING WILL MOVE BACK INTO THE WESTERN US.
THE LATEST TRENDS KEEP THE UPPER LOW AND MOST OF THE IMPACTS ACROSS
THE GREAT BASIN WITH MOSTLY SOME INCREASED WIND AND A SLIGHT CHANCE
OF PRECIPITATION FOR THE WHITE MOUNTAINS.


&&

.AVIATION...VALID THRU 20/18Z.
LINGERING PATCHY FOG AND LOW CLOUDS FROM KSAD INTO NE COCHISE COUNTY
SHOULD FINALLY DISSIPATE OR LIFT INTO SCT CLOUD DECKS BY 19/21Z.
THESE AREAS COULD SEE REDEVELOPMENT OF PATCHY FOG AFT 20/09Z
ALTHOUGH IT SHOULD NOT NEARLY AS PREVALENT AS IT WAS THIS EARLY THIS
MORNING. OTHERWISE CLEAR SKIES AND SURFACE WIND LESS THAN 10 KTS
WILL PREVAIL THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE
TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY
AFFECT THE REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR
VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...KD









000
FXUS65 KTWC 191924 AAA
AFDTWC

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE TUCSON AZ
1225 PM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.UPDATE...AVIATION SECTION UPDATE ONLY. SEE BELOW.

&&

.DISCUSSION...STILL SOME AREAS OF FOG AND FREEZING FOG SHOWING UP
CLEARLY ON VISIBLE SATELLITE THIS MORNING MAINLY IN THE RIVER
VALLEYS SUCH AS THE SANTA CRUZ...SAN PEDRO...UPPER GILA AND SAN
SIMON. SURFACE OBSERVATIONS AT NOGALES...SAFFORD AND DOUGLAS
INDICATE THAT VISIBILITIES ARE BOUNCING AROUND FROM ABOUT 1/4SM TO
2SM. AS SOLAR INSOLATION INCREASES...EXPECT FOG AND LOW CLOUDS TO
BURN OFF AS THE MORNING PROGRESSES WITH MAINLY CLEAR SKIES AREAWIDE
AFTER 11 AM.

IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT WILL MOVE INTO
ARIZONA TODAY. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS
ABOUT 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. THERE IS A
POSSIBILITY OF A FEW PATCHES OF FOG AGAIN TONIGHT/EARLY SATURDAY IN
THE MOST PRONE RIVER VALLEY LOCATIONS...BUT THIS MIGHT BE MITIGATED
BY SOME CIRROFORM CLOUDS.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WITH GRADUALLY RISING HEIGHTS AND
THICKNESS VALUES AS RIDGING ALOFT IS CENTERED ACROSS THE EASTERN
PACIFIC. THIS WILL RESULT IN A CONTINUED WARMING TEMPERATURE TREND.
BY LATE NEXT WEEK...TROUGHING WILL MOVE BACK INTO THE WESTERN US.
THE LATEST TRENDS KEEP THE UPPER LOW AND MOST OF THE IMPACTS ACROSS
THE GREAT BASIN WITH MOSTLY SOME INCREASED WIND AND A SLIGHT CHANCE
OF PRECIPITATION FOR THE WHITE MOUNTAINS.


&&

.AVIATION...VALID THRU 20/18Z.
LINGERING PATCHY FOG AND LOW CLOUDS FROM KSAD INTO NE COCHISE COUNTY
SHOULD FINALLY DISSIPATE OR LIFT INTO SCT CLOUD DECKS BY 19/21Z.
THESE AREAS COULD SEE REDEVELOPMENT OF PATCHY FOG AFT 20/09Z
ALTHOUGH IT SHOULD NOT NEARLY AS PREVALENT AS IT WAS THIS EARLY THIS
MORNING. OTHERWISE CLEAR SKIES AND SURFACE WIND LESS THAN 10 KTS
WILL PREVAIL THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE
TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY
AFFECT THE REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR
VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...KD










000
FXUS65 KTWC 191616
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
916 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...STILL SOME AREAS OF FOG AND FREEZING FOG SHOWING UP
CLEARLY ON VISIBLE SATELLITE THIS MORNING MAINLY IN THE RIVER
VALLEYS SUCH AS THE SANTA CRUZ...SAN PEDRO...UPPER GILA AND SAN
SIMON. SURFACE OBSERVATIONS AT NOGALES...SAFFORD AND DOUGLAS
INDICATE THAT VISIBILITIES ARE BOUNCING AROUND FROM ABOUT 1/4SM TO
2SM. AS SOLAR INSOLATION INCREASES...EXPECT FOG AND LOW CLOUDS TO
BURN OFF AS THE MORNING PROGRESSES WITH MAINLY CLEAR SKIES AREAWIDE
AFTER 11 AM.

IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT WILL MOVE INTO
ARIZONA TODAY. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS
ABOUT 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. THERE IS A
POSSIBILITY OF A FEW PATCHES OF FOG AGAIN TONIGHT/EARLY SATURDAY IN
THE MOST PRONE RIVER VALLEY LOCATIONS...BUT THIS MIGHT BE MITIGATED
BY SOME CIRROFORM CLOUDS.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WITH GRADUALLY RISING HEIGHTS AND
THICKNESS VALUES AS RIDGING ALOFT IS CENTERED ACROSS THE EASTERN
PACIFIC. THIS WILL RESULT IN A CONTINUED WARMING TEMPERATURE TREND.
BY LATE NEXT WEEK...TROUGHING WILL MOVE BACK INTO THE WESTERN US.
THE LATEST TRENDS KEEP THE UPPER LOW AND MOST OF THE IMPACTS ACROSS
THE GREAT BASIN WITH MOSTLY SOME INCREASED WIND AND A SLIGHT CHANCE
OF PRECIPITATION FOR THE WHITE MOUNTAINS.


&&

.AVIATION...VALID THRU 20/18Z.
LINGERING PATCHY FOG AND LOW CLOUDS FROM JUST SOUTH OF KTUS TO KOLS
AND EASTWARD TO KDUG TO KSAD SHOULD LIFT OR BURN OFF BY 19/17Z.
EASTERN AREAS COULD SEE REDEVELOPMENT OF PATCHY FOG AFT 20/09Z
ALTHOUGH IT SHOULD NOT NEARLY AS PREVALENT AS IT WAS THIS EARLY THIS
MORNING. OTHERWISE CLEAR SKIES AND SURFACE WIND LESS THAN 10 KTS
WILL PREVAIL THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE
TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY
AFFECT THE REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR
VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...KD






000
FXUS65 KTWC 191616
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
916 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...STILL SOME AREAS OF FOG AND FREEZING FOG SHOWING UP
CLEARLY ON VISIBLE SATELLITE THIS MORNING MAINLY IN THE RIVER
VALLEYS SUCH AS THE SANTA CRUZ...SAN PEDRO...UPPER GILA AND SAN
SIMON. SURFACE OBSERVATIONS AT NOGALES...SAFFORD AND DOUGLAS
INDICATE THAT VISIBILITIES ARE BOUNCING AROUND FROM ABOUT 1/4SM TO
2SM. AS SOLAR INSOLATION INCREASES...EXPECT FOG AND LOW CLOUDS TO
BURN OFF AS THE MORNING PROGRESSES WITH MAINLY CLEAR SKIES AREAWIDE
AFTER 11 AM.

IN THE LARGER SCALE...WEAK SHORTWAVE RIDGING ALOFT WILL MOVE INTO
ARIZONA TODAY. TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH HIGHS
ABOUT 5 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. THERE IS A
POSSIBILITY OF A FEW PATCHES OF FOG AGAIN TONIGHT/EARLY SATURDAY IN
THE MOST PRONE RIVER VALLEY LOCATIONS...BUT THIS MIGHT BE MITIGATED
BY SOME CIRROFORM CLOUDS.

A WEAK SHORTWAVE TROUGH WILL SKIRT ACROSS MAINLY EASTERN SECTIONS OF
THE FORECAST AREA ON SATURDAY WITH LITTLE SENSIBLE WEATHER IMPACT
OTHER THEN SOME MAINLY HIGH LEVEL CLOUDS. TEMPERATURES WILL WARM A
FEW DEGREES ON SATURDAY COMPARED TO TODAY.

THEREAFTER...DRY NORTHWESTERLY FLOW ALOFT IS EXPECTED FROM SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WITH GRADUALLY RISING HEIGHTS AND
THICKNESS VALUES AS RIDGING ALOFT IS CENTERED ACROSS THE EASTERN
PACIFIC. THIS WILL RESULT IN A CONTINUED WARMING TEMPERATURE TREND.
BY LATE NEXT WEEK...TROUGHING WILL MOVE BACK INTO THE WESTERN US.
THE LATEST TRENDS KEEP THE UPPER LOW AND MOST OF THE IMPACTS ACROSS
THE GREAT BASIN WITH MOSTLY SOME INCREASED WIND AND A SLIGHT CHANCE
OF PRECIPITATION FOR THE WHITE MOUNTAINS.


&&

.AVIATION...VALID THRU 20/18Z.
LINGERING PATCHY FOG AND LOW CLOUDS FROM JUST SOUTH OF KTUS TO KOLS
AND EASTWARD TO KDUG TO KSAD SHOULD LIFT OR BURN OFF BY 19/17Z.
EASTERN AREAS COULD SEE REDEVELOPMENT OF PATCHY FOG AFT 20/09Z
ALTHOUGH IT SHOULD NOT NEARLY AS PREVALENT AS IT WAS THIS EARLY THIS
MORNING. OTHERWISE CLEAR SKIES AND SURFACE WIND LESS THAN 10 KTS
WILL PREVAIL THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. AT THIS TIME CONFIDENCE IS LOW CONCERNING THE
TIMING AND IMPACTS OF THE NEXT SIGNIFICANT WEATHER MAKER WHICH MAY
AFFECT THE REGION LATE NEXT WEEK. GUSTY WINDS AND ANOTHER CHANCE FOR
VALLEY RAIN AND MOUNTAIN SNOW ARE POSSIBLE.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...GL
AVIATION/FIRE WEATHER...KD







000
FXUS65 KTWC 190922
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...SKIES CLEARED OUT LAST EVENING WHICH HAS ALLOWED
TEMPERATURES TO DROP NICELY WITH FOG BEGINNING TO FORM ACROSS FAR
EASTERN AREAS.  WITH THE CURRENT TEMP/DEWPOINT SPREADS WOULD EXPECT
THE FOG OR SOME VERY LOW CLOUDS TO CONTINUE TO DEVELOP AND BECOME
SOMEWHAT MORE WIDESPREAD MAINLY EAST AND SOUTH OF TUCSON THIS
MORNING.  THIS WILL BEGIN TO BURN OFF AN HOUR OR TWO AFTER SUNRISE
AND BE PRETTY MUCH GONE BY LATE MORNING.  WITH THE COOL AIR MASS IN
PLACE AND THE EFFECTS OF THE MORNING FOG HIGH TEMPERATURES WILL BE
3-7 DEGREES COOLER THAN NORMAL THIS AFTERNOON DESPITE THE SUNSHINE.

FOR THE WEEKEND...A COUPLE OF WEAK AND DRY SHORTWAVES WILL DROP
SOUTHEAST ACROSS THE REGION WHICH WILL PAVE THE WAY FOR NW UPPER
LEVEL FLOW EARLY NEXT WEEK.  THESE WEAK WAVES WILL BE GOOD FOR SOME
HIGH CLOUDS PASSING BY AT TIMES BUT THATS ABOUT IT.  EACH DAY WILL
BE A COUPLE OF DEGREES WARMER THAN THE PREVIOUS ONE SO THAT BY
SUNDAY TEMPERATURES WILL BE RIGHT ABOUT SEASONAL NORMS.

AN UPPER LEVEL RIDGE ALONG THE WEST COAST WILL NOSE OVER THE AREA
EARLY NEXT WEEK WHICH WILL ALLOW FOR A STEADY WARMING TREND MONDAY
THROUGH WEDNESDAY UNDER MOSTLY CLEAR SKIES.  BY WEDNESDAY AFTERNOON
TEMPERATURES WILL BE 3-7 DEGREES WARMER THAN NORMAL WITH MORNING
LOWS ANYWHERE FROM 5-10 DEGREES WARMER THAN NORMAL.

HOWEVER...THE REASON FOR THE RIDGE NOSING OVER OUR AREA IS BECAUSE A
SIGNIFICANT UPPER LEVEL TROUGH IS SHOVING IT OUT OF THE WAY AS IT
DIGS SOUTHEAST ACROSS THE WESTERN US AND WILL POTENTIALLY AFFECT OUR
AREA CHRISTMAS DAY AND FRIDAY.  THIS FEATURE HAS BEEN INDICATED IN
THE MODELS FOR THE LAST SEVERAL DAYS BUT THERE HAS BEEN A FAIR
AMOUNT OF INCONSISTENCY IN THE DEPTH OF THE TROUGH.  THE ECMWF
CONTINUES DEPICT THE DEEPEST TROUGH ALTHOUGH TODAYS SOLUTION IS A
GOOD DEAL WEAKER THAN YESTERDAY.  AT THIS POINT WENT WITH SLIGHT
CHANCE POPS OVER THE WHITE MOUNTAINS AND DROPPED TEMPERATURES BACK
SEVERAL DEGREES CHRISTMAS DAY AND FRIDAY.  IT IS LIKELY THAT WE WILL
ALSO HAVE SOME BREEZY AFTERNOON WINDS THOSE TWO DAYS.  WILL HAVE TO
WAIT AND SEE HOW THIS ALL UNFOLDS OVER THE NEXT COUPLE OF DAYS.
CERNIGLIA


&&

.AVIATION...VALID THRU 20/12Z.
MOSTLY CLEAR SKIES EARLY THIS MORNING AS THE SYSTEM THAT BROUGHT
RAIN AND MOUNTAIN SNOW CONTINUES TO EXIT THE REGION TO THE EAST.
HOWEVER...ENOUGH LINGERING LOW LEVEL MOISTURE THAT SOME TERMINALS
WILL EXPERIENCE DETERIORATING CONDITIONS DUE TO FOG AND/OR STRATUS
DEVELOPMENT...WITH IFR CONDITIONS IN SOME AREAS THIS MORNING
PARTICULARLY ALONG THE INTERNATIONAL BORDER SUCH AS KOLS AND KDUG.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER MAY ENTER THE
REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 190922
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...SKIES CLEARED OUT LAST EVENING WHICH HAS ALLOWED
TEMPERATURES TO DROP NICELY WITH FOG BEGINNING TO FORM ACROSS FAR
EASTERN AREAS.  WITH THE CURRENT TEMP/DEWPOINT SPREADS WOULD EXPECT
THE FOG OR SOME VERY LOW CLOUDS TO CONTINUE TO DEVELOP AND BECOME
SOMEWHAT MORE WIDESPREAD MAINLY EAST AND SOUTH OF TUCSON THIS
MORNING.  THIS WILL BEGIN TO BURN OFF AN HOUR OR TWO AFTER SUNRISE
AND BE PRETTY MUCH GONE BY LATE MORNING.  WITH THE COOL AIR MASS IN
PLACE AND THE EFFECTS OF THE MORNING FOG HIGH TEMPERATURES WILL BE
3-7 DEGREES COOLER THAN NORMAL THIS AFTERNOON DESPITE THE SUNSHINE.

FOR THE WEEKEND...A COUPLE OF WEAK AND DRY SHORTWAVES WILL DROP
SOUTHEAST ACROSS THE REGION WHICH WILL PAVE THE WAY FOR NW UPPER
LEVEL FLOW EARLY NEXT WEEK.  THESE WEAK WAVES WILL BE GOOD FOR SOME
HIGH CLOUDS PASSING BY AT TIMES BUT THATS ABOUT IT.  EACH DAY WILL
BE A COUPLE OF DEGREES WARMER THAN THE PREVIOUS ONE SO THAT BY
SUNDAY TEMPERATURES WILL BE RIGHT ABOUT SEASONAL NORMS.

AN UPPER LEVEL RIDGE ALONG THE WEST COAST WILL NOSE OVER THE AREA
EARLY NEXT WEEK WHICH WILL ALLOW FOR A STEADY WARMING TREND MONDAY
THROUGH WEDNESDAY UNDER MOSTLY CLEAR SKIES.  BY WEDNESDAY AFTERNOON
TEMPERATURES WILL BE 3-7 DEGREES WARMER THAN NORMAL WITH MORNING
LOWS ANYWHERE FROM 5-10 DEGREES WARMER THAN NORMAL.

HOWEVER...THE REASON FOR THE RIDGE NOSING OVER OUR AREA IS BECAUSE A
SIGNIFICANT UPPER LEVEL TROUGH IS SHOVING IT OUT OF THE WAY AS IT
DIGS SOUTHEAST ACROSS THE WESTERN US AND WILL POTENTIALLY AFFECT OUR
AREA CHRISTMAS DAY AND FRIDAY.  THIS FEATURE HAS BEEN INDICATED IN
THE MODELS FOR THE LAST SEVERAL DAYS BUT THERE HAS BEEN A FAIR
AMOUNT OF INCONSISTENCY IN THE DEPTH OF THE TROUGH.  THE ECMWF
CONTINUES DEPICT THE DEEPEST TROUGH ALTHOUGH TODAYS SOLUTION IS A
GOOD DEAL WEAKER THAN YESTERDAY.  AT THIS POINT WENT WITH SLIGHT
CHANCE POPS OVER THE WHITE MOUNTAINS AND DROPPED TEMPERATURES BACK
SEVERAL DEGREES CHRISTMAS DAY AND FRIDAY.  IT IS LIKELY THAT WE WILL
ALSO HAVE SOME BREEZY AFTERNOON WINDS THOSE TWO DAYS.  WILL HAVE TO
WAIT AND SEE HOW THIS ALL UNFOLDS OVER THE NEXT COUPLE OF DAYS.
CERNIGLIA


&&

.AVIATION...VALID THRU 20/12Z.
MOSTLY CLEAR SKIES EARLY THIS MORNING AS THE SYSTEM THAT BROUGHT
RAIN AND MOUNTAIN SNOW CONTINUES TO EXIT THE REGION TO THE EAST.
HOWEVER...ENOUGH LINGERING LOW LEVEL MOISTURE THAT SOME TERMINALS
WILL EXPERIENCE DETERIORATING CONDITIONS DUE TO FOG AND/OR STRATUS
DEVELOPMENT...WITH IFR CONDITIONS IN SOME AREAS THIS MORNING
PARTICULARLY ALONG THE INTERNATIONAL BORDER SUCH AS KOLS AND KDUG.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER MAY ENTER THE
REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 190922
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...SKIES CLEARED OUT LAST EVENING WHICH HAS ALLOWED
TEMPERATURES TO DROP NICELY WITH FOG BEGINNING TO FORM ACROSS FAR
EASTERN AREAS.  WITH THE CURRENT TEMP/DEWPOINT SPREADS WOULD EXPECT
THE FOG OR SOME VERY LOW CLOUDS TO CONTINUE TO DEVELOP AND BECOME
SOMEWHAT MORE WIDESPREAD MAINLY EAST AND SOUTH OF TUCSON THIS
MORNING.  THIS WILL BEGIN TO BURN OFF AN HOUR OR TWO AFTER SUNRISE
AND BE PRETTY MUCH GONE BY LATE MORNING.  WITH THE COOL AIR MASS IN
PLACE AND THE EFFECTS OF THE MORNING FOG HIGH TEMPERATURES WILL BE
3-7 DEGREES COOLER THAN NORMAL THIS AFTERNOON DESPITE THE SUNSHINE.

FOR THE WEEKEND...A COUPLE OF WEAK AND DRY SHORTWAVES WILL DROP
SOUTHEAST ACROSS THE REGION WHICH WILL PAVE THE WAY FOR NW UPPER
LEVEL FLOW EARLY NEXT WEEK.  THESE WEAK WAVES WILL BE GOOD FOR SOME
HIGH CLOUDS PASSING BY AT TIMES BUT THATS ABOUT IT.  EACH DAY WILL
BE A COUPLE OF DEGREES WARMER THAN THE PREVIOUS ONE SO THAT BY
SUNDAY TEMPERATURES WILL BE RIGHT ABOUT SEASONAL NORMS.

AN UPPER LEVEL RIDGE ALONG THE WEST COAST WILL NOSE OVER THE AREA
EARLY NEXT WEEK WHICH WILL ALLOW FOR A STEADY WARMING TREND MONDAY
THROUGH WEDNESDAY UNDER MOSTLY CLEAR SKIES.  BY WEDNESDAY AFTERNOON
TEMPERATURES WILL BE 3-7 DEGREES WARMER THAN NORMAL WITH MORNING
LOWS ANYWHERE FROM 5-10 DEGREES WARMER THAN NORMAL.

HOWEVER...THE REASON FOR THE RIDGE NOSING OVER OUR AREA IS BECAUSE A
SIGNIFICANT UPPER LEVEL TROUGH IS SHOVING IT OUT OF THE WAY AS IT
DIGS SOUTHEAST ACROSS THE WESTERN US AND WILL POTENTIALLY AFFECT OUR
AREA CHRISTMAS DAY AND FRIDAY.  THIS FEATURE HAS BEEN INDICATED IN
THE MODELS FOR THE LAST SEVERAL DAYS BUT THERE HAS BEEN A FAIR
AMOUNT OF INCONSISTENCY IN THE DEPTH OF THE TROUGH.  THE ECMWF
CONTINUES DEPICT THE DEEPEST TROUGH ALTHOUGH TODAYS SOLUTION IS A
GOOD DEAL WEAKER THAN YESTERDAY.  AT THIS POINT WENT WITH SLIGHT
CHANCE POPS OVER THE WHITE MOUNTAINS AND DROPPED TEMPERATURES BACK
SEVERAL DEGREES CHRISTMAS DAY AND FRIDAY.  IT IS LIKELY THAT WE WILL
ALSO HAVE SOME BREEZY AFTERNOON WINDS THOSE TWO DAYS.  WILL HAVE TO
WAIT AND SEE HOW THIS ALL UNFOLDS OVER THE NEXT COUPLE OF DAYS.
CERNIGLIA


&&

.AVIATION...VALID THRU 20/12Z.
MOSTLY CLEAR SKIES EARLY THIS MORNING AS THE SYSTEM THAT BROUGHT
RAIN AND MOUNTAIN SNOW CONTINUES TO EXIT THE REGION TO THE EAST.
HOWEVER...ENOUGH LINGERING LOW LEVEL MOISTURE THAT SOME TERMINALS
WILL EXPERIENCE DETERIORATING CONDITIONS DUE TO FOG AND/OR STRATUS
DEVELOPMENT...WITH IFR CONDITIONS IN SOME AREAS THIS MORNING
PARTICULARLY ALONG THE INTERNATIONAL BORDER SUCH AS KOLS AND KDUG.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER MAY ENTER THE
REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 190922
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 AM MST FRI DEC 19 2014

.SYNOPSIS...A DRY NORTHWEST FLOW PATTERN WILL RESULT IN SOME PASSING
HIGH LEVEL CLOUDS AND SOMEWHAT COOLER THAN NORMAL TEMPERATURES
THROUGH THE WEEKEND.  THEN TEMPERATURES WILL RISE TO ABOVE NORMAL
LEVELS THROUGH THE MIDDLE OF NEXT WEEK DUE TO A PASSING UPPER LEVEL
RIDGE.  UNSETTLED AND COOLER WEATHER LOOKS LIKELY FOR THE END OF
NEXT WEEK.

&&

.DISCUSSION...SKIES CLEARED OUT LAST EVENING WHICH HAS ALLOWED
TEMPERATURES TO DROP NICELY WITH FOG BEGINNING TO FORM ACROSS FAR
EASTERN AREAS.  WITH THE CURRENT TEMP/DEWPOINT SPREADS WOULD EXPECT
THE FOG OR SOME VERY LOW CLOUDS TO CONTINUE TO DEVELOP AND BECOME
SOMEWHAT MORE WIDESPREAD MAINLY EAST AND SOUTH OF TUCSON THIS
MORNING.  THIS WILL BEGIN TO BURN OFF AN HOUR OR TWO AFTER SUNRISE
AND BE PRETTY MUCH GONE BY LATE MORNING.  WITH THE COOL AIR MASS IN
PLACE AND THE EFFECTS OF THE MORNING FOG HIGH TEMPERATURES WILL BE
3-7 DEGREES COOLER THAN NORMAL THIS AFTERNOON DESPITE THE SUNSHINE.

FOR THE WEEKEND...A COUPLE OF WEAK AND DRY SHORTWAVES WILL DROP
SOUTHEAST ACROSS THE REGION WHICH WILL PAVE THE WAY FOR NW UPPER
LEVEL FLOW EARLY NEXT WEEK.  THESE WEAK WAVES WILL BE GOOD FOR SOME
HIGH CLOUDS PASSING BY AT TIMES BUT THATS ABOUT IT.  EACH DAY WILL
BE A COUPLE OF DEGREES WARMER THAN THE PREVIOUS ONE SO THAT BY
SUNDAY TEMPERATURES WILL BE RIGHT ABOUT SEASONAL NORMS.

AN UPPER LEVEL RIDGE ALONG THE WEST COAST WILL NOSE OVER THE AREA
EARLY NEXT WEEK WHICH WILL ALLOW FOR A STEADY WARMING TREND MONDAY
THROUGH WEDNESDAY UNDER MOSTLY CLEAR SKIES.  BY WEDNESDAY AFTERNOON
TEMPERATURES WILL BE 3-7 DEGREES WARMER THAN NORMAL WITH MORNING
LOWS ANYWHERE FROM 5-10 DEGREES WARMER THAN NORMAL.

HOWEVER...THE REASON FOR THE RIDGE NOSING OVER OUR AREA IS BECAUSE A
SIGNIFICANT UPPER LEVEL TROUGH IS SHOVING IT OUT OF THE WAY AS IT
DIGS SOUTHEAST ACROSS THE WESTERN US AND WILL POTENTIALLY AFFECT OUR
AREA CHRISTMAS DAY AND FRIDAY.  THIS FEATURE HAS BEEN INDICATED IN
THE MODELS FOR THE LAST SEVERAL DAYS BUT THERE HAS BEEN A FAIR
AMOUNT OF INCONSISTENCY IN THE DEPTH OF THE TROUGH.  THE ECMWF
CONTINUES DEPICT THE DEEPEST TROUGH ALTHOUGH TODAYS SOLUTION IS A
GOOD DEAL WEAKER THAN YESTERDAY.  AT THIS POINT WENT WITH SLIGHT
CHANCE POPS OVER THE WHITE MOUNTAINS AND DROPPED TEMPERATURES BACK
SEVERAL DEGREES CHRISTMAS DAY AND FRIDAY.  IT IS LIKELY THAT WE WILL
ALSO HAVE SOME BREEZY AFTERNOON WINDS THOSE TWO DAYS.  WILL HAVE TO
WAIT AND SEE HOW THIS ALL UNFOLDS OVER THE NEXT COUPLE OF DAYS.
CERNIGLIA


&&

.AVIATION...VALID THRU 20/12Z.
MOSTLY CLEAR SKIES EARLY THIS MORNING AS THE SYSTEM THAT BROUGHT
RAIN AND MOUNTAIN SNOW CONTINUES TO EXIT THE REGION TO THE EAST.
HOWEVER...ENOUGH LINGERING LOW LEVEL MOISTURE THAT SOME TERMINALS
WILL EXPERIENCE DETERIORATING CONDITIONS DUE TO FOG AND/OR STRATUS
DEVELOPMENT...WITH IFR CONDITIONS IN SOME AREAS THIS MORNING
PARTICULARLY ALONG THE INTERNATIONAL BORDER SUCH AS KOLS AND KDUG.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL TODAY THROUGH NEXT
WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN
THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST BREEZES
WILL OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER VALLEY
INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER MAY ENTER THE
REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 190341
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST THU DEC 18 2014

.SYNOPSIS...CLEARING AND COLDER TONIGHT WITH AREAS OF FOG POSSIBLE
AND PATCHY FROST IN EASTERN AREAS. DRYING WITH A GRADUAL WARMING
TREND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...CLEARING THIS EVENING WITH TEMPERATURES FALLING A
LITTLE FASTER THAN LAST NIGHT WITH DEW POINTS DOWN 3 TO 6 DEGREES
COMPARED TO 24 HRS AGO. ENOUGH BOUNDARY LAYER MOISTURE AROUND TO
SLOW THE DIURNAL TEMPERATURE TREND...BUT ALSO PROVIDING THE
POTENTIAL FOR SOME FOG SPOTS OVERNIGHT. COLDEST VALLEY SPOTS COULD
ALSO SEE SOME FREEZING FOG OR FROST. FORECAST TRENDS LOOK GOOD.
PLEASE SEE PREVIOUS DISCUSSION FOR ADDITIONAL DETAILS.

&&

.AVIATION...VALID THRU 20/04Z.
CLEARING TRENDS FROM THE WEST TONIGHT AS SHOWERS MOVE EAST OF THE
AREA. CANNOT RULE OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS
OCCASIONALLY DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH
AND EAST OF KTUS. SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10
KTS THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND
TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER
MAY ENTER THE REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND
ANOTHER CHANCE FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.PREV DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON
THIS AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER
LEVEL SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR
OUT. THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY
IN THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...MEYER
PREV DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81






000
FXUS65 KTWC 190341
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST THU DEC 18 2014

.SYNOPSIS...CLEARING AND COLDER TONIGHT WITH AREAS OF FOG POSSIBLE
AND PATCHY FROST IN EASTERN AREAS. DRYING WITH A GRADUAL WARMING
TREND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...CLEARING THIS EVENING WITH TEMPERATURES FALLING A
LITTLE FASTER THAN LAST NIGHT WITH DEW POINTS DOWN 3 TO 6 DEGREES
COMPARED TO 24 HRS AGO. ENOUGH BOUNDARY LAYER MOISTURE AROUND TO
SLOW THE DIURNAL TEMPERATURE TREND...BUT ALSO PROVIDING THE
POTENTIAL FOR SOME FOG SPOTS OVERNIGHT. COLDEST VALLEY SPOTS COULD
ALSO SEE SOME FREEZING FOG OR FROST. FORECAST TRENDS LOOK GOOD.
PLEASE SEE PREVIOUS DISCUSSION FOR ADDITIONAL DETAILS.

&&

.AVIATION...VALID THRU 20/04Z.
CLEARING TRENDS FROM THE WEST TONIGHT AS SHOWERS MOVE EAST OF THE
AREA. CANNOT RULE OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS
OCCASIONALLY DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH
AND EAST OF KTUS. SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10
KTS THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND
TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER
MAY ENTER THE REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND
ANOTHER CHANCE FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.PREV DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON
THIS AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER
LEVEL SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR
OUT. THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY
IN THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...MEYER
PREV DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81







000
FXUS65 KTWC 190341
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST THU DEC 18 2014

.SYNOPSIS...CLEARING AND COLDER TONIGHT WITH AREAS OF FOG POSSIBLE
AND PATCHY FROST IN EASTERN AREAS. DRYING WITH A GRADUAL WARMING
TREND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...CLEARING THIS EVENING WITH TEMPERATURES FALLING A
LITTLE FASTER THAN LAST NIGHT WITH DEW POINTS DOWN 3 TO 6 DEGREES
COMPARED TO 24 HRS AGO. ENOUGH BOUNDARY LAYER MOISTURE AROUND TO
SLOW THE DIURNAL TEMPERATURE TREND...BUT ALSO PROVIDING THE
POTENTIAL FOR SOME FOG SPOTS OVERNIGHT. COLDEST VALLEY SPOTS COULD
ALSO SEE SOME FREEZING FOG OR FROST. FORECAST TRENDS LOOK GOOD.
PLEASE SEE PREVIOUS DISCUSSION FOR ADDITIONAL DETAILS.

&&

.AVIATION...VALID THRU 20/04Z.
CLEARING TRENDS FROM THE WEST TONIGHT AS SHOWERS MOVE EAST OF THE
AREA. CANNOT RULE OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS
OCCASIONALLY DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH
AND EAST OF KTUS. SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10
KTS THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND
TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER
MAY ENTER THE REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND
ANOTHER CHANCE FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.PREV DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON
THIS AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER
LEVEL SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR
OUT. THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY
IN THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...MEYER
PREV DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81






000
FXUS65 KTWC 190341
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST THU DEC 18 2014

.SYNOPSIS...CLEARING AND COLDER TONIGHT WITH AREAS OF FOG POSSIBLE
AND PATCHY FROST IN EASTERN AREAS. DRYING WITH A GRADUAL WARMING
TREND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...CLEARING THIS EVENING WITH TEMPERATURES FALLING A
LITTLE FASTER THAN LAST NIGHT WITH DEW POINTS DOWN 3 TO 6 DEGREES
COMPARED TO 24 HRS AGO. ENOUGH BOUNDARY LAYER MOISTURE AROUND TO
SLOW THE DIURNAL TEMPERATURE TREND...BUT ALSO PROVIDING THE
POTENTIAL FOR SOME FOG SPOTS OVERNIGHT. COLDEST VALLEY SPOTS COULD
ALSO SEE SOME FREEZING FOG OR FROST. FORECAST TRENDS LOOK GOOD.
PLEASE SEE PREVIOUS DISCUSSION FOR ADDITIONAL DETAILS.

&&

.AVIATION...VALID THRU 20/04Z.
CLEARING TRENDS FROM THE WEST TONIGHT AS SHOWERS MOVE EAST OF THE
AREA. CANNOT RULE OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS
OCCASIONALLY DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH
AND EAST OF KTUS. SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10
KTS THROUGH THE PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT AND
TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER
MAY ENTER THE REGION LATE NEXT WEEK WITH POSSIBLE GUSTY WINDS AND
ANOTHER CHANCE FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.PREV DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON
THIS AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER
LEVEL SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR
OUT. THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY
IN THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON

DISCUSSION...MEYER
PREV DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81







000
FXUS65 KTWC 182135
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
235 PM MST THU DEC 18 2014

.SYNOPSIS...WEATHER SYSTEM THAT HAS BROUGHT THE RAIN AND SNOW TO
THE AREA WILL CONTINUE TO MOVE OUT THIS EVENING. THIS WILL ALLOW
SKIES TO CLEAR OUT WHICH WILL BRING THE POTENTIAL FOG EAST OF
TUCSON. FRIDAY ONWARD EXPECT DRYING AND WARMING TREND.

&&

.DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON THIS
AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER LEVEL
SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR OUT.
THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY IN
THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.AVIATION...VALID THRU 20/00Z.
SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW SHOWERS WITH PERHAPS
A FEW RUMBLES OF THUNDER WILL CONTINUE TO MOVE EAST THIS AFTERNOON...WITH
LOCAL MVFR CONDITIONS OCCURRING ESPECIALLY ACROSS THE HIGHER TERRAIN
AND NEAR PRECIPITATION. SHOWERS WILL DECREASE FROM WEST TO EAST THIS
EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO FRIDAY. CLOUD
DECKS WILL INITIALLY RANGE FROM 3-6K FT AGL...GRADUALLY LIFTING AND
DISSIPATING LATE THIS EVENING AND INTO FRIDAY MORNING. CANNOT RULE
OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS OCCASIONALLY
DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH AND EAST OF KTUS.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...VALLEY RAIN AND MOUNTAIN SNOW SHOWERS WILL TAPER OFF
FROM WEST TO EAST THIS EVENING. DRY CONDITIONS WILL PREVAIL LATE
TONIGHT THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT
AND TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER WILL
ENTER THE REGION LATE NEXT WEEK WITH GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81

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000
FXUS65 KTWC 182135
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
235 PM MST THU DEC 18 2014

.SYNOPSIS...WEATHER SYSTEM THAT HAS BROUGHT THE RAIN AND SNOW TO
THE AREA WILL CONTINUE TO MOVE OUT THIS EVENING. THIS WILL ALLOW
SKIES TO CLEAR OUT WHICH WILL BRING THE POTENTIAL FOG EAST OF
TUCSON. FRIDAY ONWARD EXPECT DRYING AND WARMING TREND.

&&

.DISCUSSION...BROAD AREA OF SHOWERS SOUTH AND EAST OF TUCSON THIS
AFTERNOON WILL CONTINUE TO MOVE OFF TO THE EAST AS THE UPPER LEVEL
SHORTWAVE TROUGH EXITS. AS THIS OCCURS EXPECT SKIES TO CLEAR OUT.
THIS WILL BRING THE POTENTIAL FOR FOG DEVELOPMENT... ESPECIALLY IN
THE VALLEY LOCATION EAST OF TUCSON. FOR THESE LOCATION HAVE ALSO
INTRODUCED FREEZING FOG MENTION AS TEMPERATURES WILL LIKELY DROP
BELOW FREEZING OVERNIGHT.

HAVE CONTINUED THE FOG MENTION ACROSS THE CITY OF TUCSON AND
SOUTHWARD...THOUGH IF THE AREA CONTINUES TO DRY OUT THIS AFTERNOON
THIS MAYBE NOT HAPPEN. THE OTHER CONCERN FOR TUCSON AND SOUTH WILL
BE FROST POTENTIAL AS DEW POINTS WILL REMAIN UP WITH TEMPERATURES
EXPECTED TO DROP TO NEAR FREEZING. AT THIS TIME...IT LOOKS LIKE IT
WILL NOT BE VERY WIDESPREAD...NO HEADLINES EXPECTED AT THIS TIME.
NEVERTHELESS...OUTLYING AREAS COULD EXPERIENCE SOME FROST IN THE
AM.

FRIDAY AFTERNOON ONWARD...THINGS LOOK LIKE THEY WILL DRY OUT
RATHER QUICKLY. THIS WILL ALLOW FOR A GRADUAL WARM UP THROUGHOUT
THE WEEK. THOUGH...THE TAIL END OF THE FORECAST THE CONFIDENCE IS
LOW. AS BY CHRISTMAS GUIDANCE HAS AN UPPER TROUGH EDGING THROUGH
THE WESTERN STATES. THERE IS SOME CONSENSUS NOW AS EC HAS TRENDED
TOWARDS THE GFS IN IT BEING FAIRLY PROGRESSIVE. THIS WILL LIMIT
MUCH IN THE WAY OF COLD AIR AND MOISTURE SLIDING INTO THE AREA.
STILL...QUITE A BIT OF TIME FOR THINGS TO EVOLVE SO STAY TUNED.

&&

.AVIATION...VALID THRU 20/00Z.
SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW SHOWERS WITH PERHAPS
A FEW RUMBLES OF THUNDER WILL CONTINUE TO MOVE EAST THIS AFTERNOON...WITH
LOCAL MVFR CONDITIONS OCCURRING ESPECIALLY ACROSS THE HIGHER TERRAIN
AND NEAR PRECIPITATION. SHOWERS WILL DECREASE FROM WEST TO EAST THIS
EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO FRIDAY. CLOUD
DECKS WILL INITIALLY RANGE FROM 3-6K FT AGL...GRADUALLY LIFTING AND
DISSIPATING LATE THIS EVENING AND INTO FRIDAY MORNING. CANNOT RULE
OUT AREAS OF PATCHY FOG FRIDAY MORNING WITH VSBYS OCCASIONALLY
DROPPING BELOW 2 SM ESPECIALLY IN VALLEY AREAS SOUTH AND EAST OF KTUS.
SURFACE WIND WILL GENERALLY REMAIN LESS THAN 10 KTS THROUGH THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...VALLEY RAIN AND MOUNTAIN SNOW SHOWERS WILL TAPER OFF
FROM WEST TO EAST THIS EVENING. DRY CONDITIONS WILL PREVAIL LATE
TONIGHT THROUGH NEXT WEDNESDAY. 20-FT WINDS WILL GENERALLY BE LIGHT
AND TERRAIN DRIVEN THROUGH THE MIDDLE OF NEXT WEEK. HOWEVER...SOME
NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. THE NEXT SIGNIFICANT WEATHER MAKER WILL
ENTER THE REGION LATE NEXT WEEK WITH GUSTY WINDS AND ANOTHER CHANCE
FOR VALLEY RAIN AND MOUNTAIN SNOW.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS
FIRE WEATHER/AVIATION...81

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 182108
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
832 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...LAST IN THE SERIES OF IMPULSES THAT HAS BROUGHT SHOWERS
TO THE AREA IS MOVING INTO THE AREA THIS MORNING. SEEING SOME
CLEARING ON THE WEST HALF OF THE SYSTEM WITH DENSE CLOUD COVER
EAST. THE TRAILING END OF THE CLOUD COVER WILL MAKES ITS WAY TO
TUCSON OVER THE NEXT HOUR OR SO. HOWEVER...EXPECT CLOUDS TO FILL
BACK IN SOME AS SHOWERS SPREAD DURING THE AFTERNOON HOURS. THE
MAIN AREA FOR SHOWERS TODAY NEVERTHELESS LOOKS TO BE TUCSON
EASTWARD...WITH A WEST TO EAST CLEARING IN THE LATE AFTERNOON.
EXPECT MOST ACTIVITY TO END BY LATE EVENING. THIS AFTERNOON THERE
LOOKS TO BE ENOUGH INSTABILITY IN PLACE FOR SOME CONVECTIVELY
ENHANCED SHOWERS TO DEVELOP...WHICH WILL BRING LOCALLY HEAVIER
AMOUNTS OF PRECIPITATION. THE MAIN AREA OF CONCERN FOR THIS
CONVECTION WILL BE AGAIN NEAR THE MOUNTAINS AROUND TUCSON. THERE
IS LESS INSTABILITY EAST BUT STILL COULD SEE SOME ENHANCEMENT.

AS THINGS CLEAR OUT TONIGHT THE CONCERN WILL BE FOG DEVELOPMENT
ESPECIALLY IN THE EASTERN VALLEYS. THIS IS CURRENTLY HANDLED WELL
IN THE FORECAST...THOUGH WILL BE GIVE EXTRA ATTENTION WITH
AFTERNOON PACKAGE. OTHERWISE...THINGS WILL BEGIN TO DRY OUT FOR
THE REMAINDER OF THE FORECAST...WITH THE EXCEPTION OF CHRISTMAS
DAY AND INTO THE WEEKEND. THIS IS DUE TO ANOTHER UPPER LEVEL
SYSTEM PROGGED TO SLIDE DOWN THE WESTERN STATES. STAY TUNED.

&&

.AVIATION...VALID THRU 19/12Z. ISOLATED TO SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR MAINLY EAST OF KTUS THRU
MID-MORNING. SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY AND CONTINUE INTO
THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL OCCUR ESPECIALLY
ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO
EARLY FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM
3-6K FT AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT
OCCASIONAL VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS
AFTERNOON. GRADUAL CLEARING WILL OCCUR THIS EVENING INTO EARLY
FRIDAY MORNING. SURFACE WIND WILL MOSTLY BE LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM
OF VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS
6000 FT WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET.
THE VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST
THIS EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN
WINDS DURING MUCH OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK.
HOWEVER...SOME NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS
THE UPPER GILA RIVER VALLEY INCLUDING SAFFORD. DAYTIME
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY FOLLOWED BY A GRADUAL
WARMING TREND FRIDAY INTO THE MIDDLE OF NEXT WEEK. FRANCIS



&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON














000
FXUS65 KTWC 182108
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
832 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...LAST IN THE SERIES OF IMPULSES THAT HAS BROUGHT SHOWERS
TO THE AREA IS MOVING INTO THE AREA THIS MORNING. SEEING SOME
CLEARING ON THE WEST HALF OF THE SYSTEM WITH DENSE CLOUD COVER
EAST. THE TRAILING END OF THE CLOUD COVER WILL MAKES ITS WAY TO
TUCSON OVER THE NEXT HOUR OR SO. HOWEVER...EXPECT CLOUDS TO FILL
BACK IN SOME AS SHOWERS SPREAD DURING THE AFTERNOON HOURS. THE
MAIN AREA FOR SHOWERS TODAY NEVERTHELESS LOOKS TO BE TUCSON
EASTWARD...WITH A WEST TO EAST CLEARING IN THE LATE AFTERNOON.
EXPECT MOST ACTIVITY TO END BY LATE EVENING. THIS AFTERNOON THERE
LOOKS TO BE ENOUGH INSTABILITY IN PLACE FOR SOME CONVECTIVELY
ENHANCED SHOWERS TO DEVELOP...WHICH WILL BRING LOCALLY HEAVIER
AMOUNTS OF PRECIPITATION. THE MAIN AREA OF CONCERN FOR THIS
CONVECTION WILL BE AGAIN NEAR THE MOUNTAINS AROUND TUCSON. THERE
IS LESS INSTABILITY EAST BUT STILL COULD SEE SOME ENHANCEMENT.

AS THINGS CLEAR OUT TONIGHT THE CONCERN WILL BE FOG DEVELOPMENT
ESPECIALLY IN THE EASTERN VALLEYS. THIS IS CURRENTLY HANDLED WELL
IN THE FORECAST...THOUGH WILL BE GIVE EXTRA ATTENTION WITH
AFTERNOON PACKAGE. OTHERWISE...THINGS WILL BEGIN TO DRY OUT FOR
THE REMAINDER OF THE FORECAST...WITH THE EXCEPTION OF CHRISTMAS
DAY AND INTO THE WEEKEND. THIS IS DUE TO ANOTHER UPPER LEVEL
SYSTEM PROGGED TO SLIDE DOWN THE WESTERN STATES. STAY TUNED.

&&

.AVIATION...VALID THRU 19/12Z. ISOLATED TO SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR MAINLY EAST OF KTUS THRU
MID-MORNING. SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY AND CONTINUE INTO
THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL OCCUR ESPECIALLY
ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO
EARLY FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM
3-6K FT AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT
OCCASIONAL VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS
AFTERNOON. GRADUAL CLEARING WILL OCCUR THIS EVENING INTO EARLY
FRIDAY MORNING. SURFACE WIND WILL MOSTLY BE LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM
OF VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS
6000 FT WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET.
THE VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST
THIS EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN
WINDS DURING MUCH OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK.
HOWEVER...SOME NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS
THE UPPER GILA RIVER VALLEY INCLUDING SAFFORD. DAYTIME
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY FOLLOWED BY A GRADUAL
WARMING TREND FRIDAY INTO THE MIDDLE OF NEXT WEEK. FRANCIS



&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON













000
FXUS65 KTWC 182049
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
832 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...LAST IN THE SERIES OF IMPULSES THAT HAS BROUGHT SHOWERS
TO THE AREA IS MOVING INTO THE AREA THIS MORNING. SEEING SOME
CLEARING ON THE WEST HALF OF THE SYSTEM WITH DENSE CLOUD COVER
EAST. THE TRAILING END OF THE CLOUD COVER WILL MAKES ITS WAY TO
TUCSON OVER THE NEXT HOUR OR SO. HOWEVER...EXPECT CLOUDS TO FILL
BACK IN SOME AS SHOWERS SPREAD DURING THE AFTERNOON HOURS. THE
MAIN AREA FOR SHOWERS TODAY NEVERTHELESS LOOKS TO BE TUCSON
EASTWARD...WITH A WEST TO EAST CLEARING IN THE LATE AFTERNOON.
EXPECT MOST ACTIVITY TO END BY LATE EVENING. THIS AFTERNOON THERE
LOOKS TO BE ENOUGH INSTABILITY IN PLACE FOR SOME CONVECTIVELY
ENHANCED SHOWERS TO DEVELOP...WHICH WILL BRING LOCALLY HEAVIER
AMOUNTS OF PRECIPITATION. THE MAIN AREA OF CONCERN FOR THIS
CONVECTION WILL BE AGAIN NEAR THE MOUNTAINS AROUND TUCSON. THERE
IS LESS INSTABILITY EAST BUT STILL COULD SEE SOME ENHANCEMENT.

AS THINGS CLEAR OUT TONIGHT THE CONCERN WILL BE FOG DEVELOPMENT
ESPECIALLY IN THE EASTERN VALLEYS. THIS IS CURRENTLY HANDLED WELL
IN THE FORECAST...THOUGH WILL BE GIVE EXTRA ATTENTION WITH
AFTERNOON PACKAGE. OTHERWISE...THINGS WILL BEGIN TO DRY OUT FOR
THE REMAINDER OF THE FORECAST...WITH THE EXCEPTION OF CHRISTMAS
DAY AND INTO THE WEEKEND. THIS IS DUE TO ANOTHER UPPER LEVEL
SYSTEM PROGGED TO SLIDE DOWN THE WESTERN STATES. STAY TUNED.

&&

.AVIATION...VALID THRU 19/12Z. ISOLATED TO SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR MAINLY EAST OF KTUS THRU
MID-MORNING. SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY AND CONTINUE INTO
THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL OCCUR ESPECIALLY
ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO
EARLY FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM
3-6K FT AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT
OCCASIONAL VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS
AFTERNOON. GRADUAL CLEARING WILL OCCUR THIS EVENING INTO EARLY
FRIDAY MORNING. SURFACE WIND WILL MOSTLY BE LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM
OF VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS
6000 FT WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET.
THE VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST
THIS EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN
WINDS DURING MUCH OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK.
HOWEVER...SOME NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS
THE UPPER GILA RIVER VALLEY INCLUDING SAFFORD. DAYTIME
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY FOLLOWED BY A GRADUAL
WARMING TREND FRIDAY INTO THE MIDDLE OF NEXT WEEK. FRANCIS



&&

.PREV DISCUSSION... /ISSUED 215 AM MST THU DEC 18 2014/

JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH SOME FOG
DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

DISCUSSION...MEADOWS

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON











000
FXUS65 KTWC 181532
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
832 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...LAST IN THE SERIES OF IMPULSES THAT HAS BROUGHT SHOWERS
TO THE AREA IS MOVING INTO THE AREA THIS MORNING. SEEING SOME
CLEARING ON THE WEST HALF OF THE SYSTEM WITH DENSE CLOUD COVER
EAST. THE TRAILING END OF THE CLOUD COVER WILL MAKES ITS WAY TO
TUCSON OVER THE NEXT HOUR OR SO. HOWEVER...EXPECT CLOUDS TO FILL
BACK IN SOME AS SHOWERS SPREAD DURING THE AFTERNOON HOURS. THE
MAIN AREA FOR SHOWERS TODAY NEVERTHELESS LOOKS TO BE TUCSON
EASTWARD...WITH A WEST TO EAST CLEARING IN THE LATE AFTERNOON.
EXPECT MOST ACTIVITY TO END BY LATE EVENING. THIS AFTERNOON THERE
LOOKS TO BE ENOUGH INSTABILITY IN PLACE FOR SOME CONVECTIVELY
ENHANCED SHOWERS TO DEVELOP...WHICH WILL BRING LOCALLY HEAVIER
AMOUNTS OF PRECIPITATION. THE MAIN AREA OF CONCERN FOR THIS
CONVECTION WILL BE AGAIN NEAR THE MOUNTAINS AROUND TUCSON. THERE
IS LESS INSTABILITY EAST BUT STILL COULD SEE SOME ENHANCEMENT.

AS THINGS CLEAR OUT TONIGHT THE CONCERN WILL BE FOG DEVELOPMENT
ESPECIALLY IN THE EASTERN VALLEYS. THIS IS CURRENTLY HANDLED WELL
IN THE FORECAST...THOUGH WILL BE GIVE EXTRA ATTENTION WITH
AFTERNOON PACKAGE. OTHERWISE...THINGS WILL BEGIN TO DRY OUT FOR
THE REMAINDER OF THE FORECAST...WITH THE EXCEPTION OF CHRISTMAS
DAY AND INTO THE WEEKEND. THIS IS DUE TO ANOTHER UPPER LEVEL
SYSTEM PROGGED TO SLIDE DOWN THE WESTERN STATES. STAY TUNED.

&&

.AVIATION...VALID THRU 19/12Z. ISOLATED TO SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR MAINLY EAST OF KTUS THRU
MID-MORNING. SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY AND CONTINUE INTO
THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL OCCUR ESPECIALLY
ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO
EARLY FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM
3-6K FT AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT
OCCASIONAL VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS
AFTERNOON. GRADUAL CLEARING WILL OCCUR THIS EVENING INTO EARLY
FRIDAY MORNING. SURFACE WIND WILL MOSTLY BE LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM
OF VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS
6000 FT WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET.
THE VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST
THIS EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN
WINDS DURING MUCH OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK.
HOWEVER...SOME NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS
THE UPPER GILA RIVER VALLEY INCLUDING SAFFORD. DAYTIME
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY FOLLOWED BY A GRADUAL
WARMING TREND FRIDAY INTO THE MIDDLE OF NEXT WEEK. FRANCIS



&&

.PREV DISCUSSION... /ISSUED 215 AM MST THU DEC 18 2014/

DISCUSSION...JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH
SOME FOG DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

DISCUSSION...MEADOWS

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 181532
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
832 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...LAST IN THE SERIES OF IMPULSES THAT HAS BROUGHT SHOWERS
TO THE AREA IS MOVING INTO THE AREA THIS MORNING. SEEING SOME
CLEARING ON THE WEST HALF OF THE SYSTEM WITH DENSE CLOUD COVER
EAST. THE TRAILING END OF THE CLOUD COVER WILL MAKES ITS WAY TO
TUCSON OVER THE NEXT HOUR OR SO. HOWEVER...EXPECT CLOUDS TO FILL
BACK IN SOME AS SHOWERS SPREAD DURING THE AFTERNOON HOURS. THE
MAIN AREA FOR SHOWERS TODAY NEVERTHELESS LOOKS TO BE TUCSON
EASTWARD...WITH A WEST TO EAST CLEARING IN THE LATE AFTERNOON.
EXPECT MOST ACTIVITY TO END BY LATE EVENING. THIS AFTERNOON THERE
LOOKS TO BE ENOUGH INSTABILITY IN PLACE FOR SOME CONVECTIVELY
ENHANCED SHOWERS TO DEVELOP...WHICH WILL BRING LOCALLY HEAVIER
AMOUNTS OF PRECIPITATION. THE MAIN AREA OF CONCERN FOR THIS
CONVECTION WILL BE AGAIN NEAR THE MOUNTAINS AROUND TUCSON. THERE
IS LESS INSTABILITY EAST BUT STILL COULD SEE SOME ENHANCEMENT.

AS THINGS CLEAR OUT TONIGHT THE CONCERN WILL BE FOG DEVELOPMENT
ESPECIALLY IN THE EASTERN VALLEYS. THIS IS CURRENTLY HANDLED WELL
IN THE FORECAST...THOUGH WILL BE GIVE EXTRA ATTENTION WITH
AFTERNOON PACKAGE. OTHERWISE...THINGS WILL BEGIN TO DRY OUT FOR
THE REMAINDER OF THE FORECAST...WITH THE EXCEPTION OF CHRISTMAS
DAY AND INTO THE WEEKEND. THIS IS DUE TO ANOTHER UPPER LEVEL
SYSTEM PROGGED TO SLIDE DOWN THE WESTERN STATES. STAY TUNED.

&&

.AVIATION...VALID THRU 19/12Z. ISOLATED TO SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR MAINLY EAST OF KTUS THRU
MID-MORNING. SCATTERED TO NUMEROUS VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY AND CONTINUE INTO
THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL OCCUR ESPECIALLY
ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO
EARLY FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM
3-6K FT AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT
OCCASIONAL VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS
AFTERNOON. GRADUAL CLEARING WILL OCCUR THIS EVENING INTO EARLY
FRIDAY MORNING. SURFACE WIND WILL MOSTLY BE LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM
OF VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS
6000 FT WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET.
THE VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST
THIS EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT
THROUGH NEXT WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN
WINDS DURING MUCH OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK.
HOWEVER...SOME NORTHWEST BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS
THE UPPER GILA RIVER VALLEY INCLUDING SAFFORD. DAYTIME
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY FOLLOWED BY A GRADUAL
WARMING TREND FRIDAY INTO THE MIDDLE OF NEXT WEEK. FRANCIS



&&

.PREV DISCUSSION... /ISSUED 215 AM MST THU DEC 18 2014/

DISCUSSION...JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH
SOME FOG DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

DISCUSSION...MEADOWS

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON







000
FXUS65 KTWC 180915
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
215 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH
SOME FOG DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.AVIATION...VALID THRU 19/12Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR
MAINLY EAST OF KTUS THRU MID-MORNING. SCATTERED TO NUMEROUS VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY
AND CONTINUE INTO THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL
OCCUR ESPECIALLY ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO EARLY
FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM 3-6K FT
AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT OCCASIONAL
VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS AFTERNOON. GRADUAL
CLEARING WILL OCCUR THIS EVENING INTO EARLY FRIDAY MORNING. SURFACE
WIND WILL MOSTLY BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.  FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM OF
VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET. THE
VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST THIS
EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT THROUGH NEXT
WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN WINDS DURING MUCH
OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST
BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER
VALLEY INCLUDING SAFFORD. DAYTIME TEMPERATURES WILL BE WELL BELOW
NORMAL TODAY FOLLOWED BY A GRADUAL WARMING TREND FRIDAY INTO THE
MIDDLE OF NEXT WEEK.  FRANCIS
&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 180915
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
215 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH
SOME FOG DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.AVIATION...VALID THRU 19/12Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR
MAINLY EAST OF KTUS THRU MID-MORNING. SCATTERED TO NUMEROUS VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY
AND CONTINUE INTO THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL
OCCUR ESPECIALLY ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO EARLY
FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM 3-6K FT
AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT OCCASIONAL
VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS AFTERNOON. GRADUAL
CLEARING WILL OCCUR THIS EVENING INTO EARLY FRIDAY MORNING. SURFACE
WIND WILL MOSTLY BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.  FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM OF
VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET. THE
VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST THIS
EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT THROUGH NEXT
WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN WINDS DURING MUCH
OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST
BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER
VALLEY INCLUDING SAFFORD. DAYTIME TEMPERATURES WILL BE WELL BELOW
NORMAL TODAY FOLLOWED BY A GRADUAL WARMING TREND FRIDAY INTO THE
MIDDLE OF NEXT WEEK.  FRANCIS
&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON








000
FXUS65 KTWC 180915
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
215 AM MST THU DEC 18 2014

.SYNOPSIS...THE FINAL WEATHER SYSTEM IN THIS LATEST SERIES WILL MOVE
ACROSS THE REGION TODAY WITH ANOTHER ROUND OF SHOWERS DEVELOPING
LATER THIS MORNING AND CONTINUING INTO THE AFTERNOON.  THE SHOWERS
WILL END THIS EVENING WITH AREAS OF FOG DEVELOPING FOR FRIDAY
MORNING.  DRY CONDITIONS ARE THEN EXPECTED INTO THE MIDDLE OF NEXT
WEEK WITH TEMPERATURES GRADUALLY WARMING TO SLIGHTLY ABOVE NORMAL
LEVELS BY WEDNESDAY.

&&

.DISCUSSION...JUST A FEW ISOLATED SHOWERS AROUND THIS HOUR WITH
SOME FOG DEVELOPING HERE AND THERE.  THIS WILL CHANGE AS THE MORNING
PROGRESSES...ESPECIALLY AFTER SUNRISE.  FINAL SHORTWAVE CURRENTLY
ROTATING AROUND THE BOTTOM OF THE LONGWAVE TROUGH WILL MOVE ACROSS
THE REGION THROUGH THE DAY RESULTING IN PRECIPITATION BLOSSOMING
OVER THE CENTRAL PART OF THE CWA LATER THIS MORNING THEN EXPANDING
AS IT MOVES OFF TO THE EAST THROUGH THE AFTERNOON.  AROUND MID
AFTERNOON EXPECT SHOWERS TO BE OCCURRING FROM THE TUCSON AREA
EASTWARD WITH SNOW FALLING ABOVE ABOUT 6500-7000 FT.  BY
SUNSET...SHOWERS WILL BE CONFINED TO COCHISE...GRAHAM AND GREENLEE
COUNTIES AS IT PUSHES EAST AND ENDING ALL AREAS BY/AROUND MIDNIGHT.

I RAISED THE QPF A BIT FROM WHAT WAS IN THE GRIDS EARLIER WITH THE
FOCUS SOUTH AND EAST OF TUCSON FOR A GENERAL 0.10-0.30 OVER THE
VALLEY AREAS AND AND 0.25-0.50 OVER THE MOUNTAINS.  FOR SNOWFALL...I
WOULD EXPECT AN ADDITIONAL 2-4 INCHES OVER MOST OF THE MOUNTAIN
AREAS WITH LOCAL ACCUMULATIONS PUSHING 6 INCHES TODAY INTO THE
EVENING.

AFTER THE PRECIPITATION ENDS LATER TONIGHT THE SKIES WILL BEGIN TO
CLEAR OUT WHICH AFTER 48 HOURS OF WETNESS...SHOULD ALLOW FOR AREAS
OF FOG TO FORM LATE TONIGHT INTO FRIDAY MORNING SO I TWEAKED THE
GRIDS FROM PATCHY VALLEY FOG TO AREAS OF VALLEY FOG.  POTENTIAL FOR
SOME LOCALLY DENSE FOG IN THE FAVORED COLDER VALLEYS EAST OF TUCSON
SO TOSSED IN PATCHY DENSE FOG AMONGST THE AREAS OF FOG.  WITH THE
FOG AND COLD AIR MASS STILL IN PLACE FRIDAY WILL HAVE BELOW NORMAL
HIGH TEMPERATURES FOR ANOTHER DAY.

THEN SATURDAY A RATHER WEAK SHORTWAVE WILL DROP SE ACROSS THE AREA
BUT THIS FEATURE SHOULD ONLY PRODUCE A FEW MID AND HIGH CLOUDS AS IT
PASSES.  HOWEVER...THIS WILL TRANSITION THE FLOW ALOFT TO NW FROM
SUNDAY THROUGH WEDNESDAY WITH HEIGHTS RISING RESULTING IN MOSTLY
CLEAR SKIES AND WARMING TEMPERATURES REACHING A FEW DEGREES WARMER
THAN NORMAL BY TUESDAY AND WEDNESDAY.

BEYOND THAT...LONG RANGE MODELS BEGINNING TO ADVERTISE THE POTENTIAL
FOR ANOTHER DECENT TROUGH TO MOVE THROUGH OR NEARBY THE AREA NEXT
THURSDAY AND/OR FRIDAY FOR ANOTHER CHANCE OF PRECIPITATION.
CERNIGLIA

&&

.AVIATION...VALID THRU 19/12Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL OCCUR
MAINLY EAST OF KTUS THRU MID-MORNING. SCATTERED TO NUMEROUS VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL THEN DEVELOP AROUND 15Z-17Z TODAY
AND CONTINUE INTO THIS AFTERNOON. AREAS OF MVFR CONDITIONS WILL
OCCUR ESPECIALLY ACROSS THE HIGHER TERRAIN AND WITH HEAVIER PRECIP.
THEREAFTER...VALLEY RAIN/MOUNTAIN SNOW WILL DECREASE FROM WEST TO
EAST THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT INTO EARLY
FRIDAY MORNING. CLOUD DECKS TODAY WILL GENERALLY RANGE FROM 3-6K FT
AGL...THOUGH BASES LESS THAN 1K FT AGL WILL OCCUR. EXPECT OCCASIONAL
VSBYS REDUCED TO LESS THAN 1SM IN FOG THRU THIS AFTERNOON. GRADUAL
CLEARING WILL OCCUR THIS EVENING INTO EARLY FRIDAY MORNING. SURFACE
WIND WILL MOSTLY BE LESS THAN 10 KTS. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.  FRANCIS

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE TODAY IN THE FORM OF
VALLEY RAIN AND MOUNTAIN SNOW. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH SEVERAL INCHES OF SNOW ACCUMULATIONS ABOVE 7000 FEET. THE
VALLEY RAIN AND MOUNTAIN SNOW WILL DECREASE FROM WEST TO EAST THIS
EVENING...THEN DRY CONDITIONS WILL PREVAIL LATE TONIGHT THROUGH NEXT
WEDNESDAY. EXPECT GENERALLY LIGHT TERRAIN DRIVEN WINDS DURING MUCH
OF THE PERIOD INTO THE MIDDLE OF NEXT WEEK. HOWEVER...SOME NORTHWEST
BREEZES MAY OCCUR MONDAY AFTERNOON ACROSS THE UPPER GILA RIVER
VALLEY INCLUDING SAFFORD. DAYTIME TEMPERATURES WILL BE WELL BELOW
NORMAL TODAY FOLLOWED BY A GRADUAL WARMING TREND FRIDAY INTO THE
MIDDLE OF NEXT WEEK.  FRANCIS
&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON









000
FXUS65 KTWC 180338
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST WED DEC 17 2014

.SYNOPSIS...AFTER A PARTIAL BREAK IN THE EARLY MORNING HOURS...A LOW
PRESSURE SYSTEM WILL CONTINUE TO BRING PERIODS OF VALLEY RAIN AND
MOUNTAIN SNOW TO THE AREA THROUGH THURSDAY EVENING. SEASONABLY COOL
THE NEXT FEW NIGHTS...OTHERWISE EXPECT DRIER CONDITIONS WITH A
GRADUAL WARMING TREND INTO CHRISTMAS EVE.

&&

.DISCUSSION...SOLID SHOT OF VALLEY RAIN AND MOUNTAIN SNOW THIS
AFTERNOON AND EVENING. WIDESPREAD RAINFALL AMOUNTS IN THE .3 TO .6
OF AN INCH RANGE ACROSS TUCSON METRO. FIRST IMPULSE LAST NIGHT
LOWERED OUR SNOW LEVELS SO THAT ELEVATIONS ABOVE 7500 FEET STARTED
WITH SNOW INSTEAD OF RAIN WITH THIS SECOND STRONGER IMPULSE DURING
THE AFTERNOON HOURS. REPORTS OF 4 TO 5 INCHES OF SNOW AT SUMMERHAVEN
AS OF 4:30 PM JUST BEFORE A SECOND BAND OF MODERATE SHOWERS MOVED
THROUGH THE AREA. STILL SOME LIGHT TO MODERATE ACTIVITY UP THERE AS
OF 830 PM BUT SLOWING CONSIDERABLY FROM WEST TO EAST. CAMERAS ON MT
GRAHAM INDICATED 5 TO 6 INCHES OF SNOW AT AN ADOT YARD RIGHT AT
SUNSET AND THE SNOTEL SENSOR AT HANNAGAN MEADOWS WAS AT 4 INCHES AS
OF 7PM. WE WILL PROBABLY BE ABLE TO CANCEL THE SNOW ADVISORY EARLY
FOR THOSE LOCATIONS...AS WE SHOULD CONTINUE TO SEE A DECREASE IN
COVERAGE AND INTENSITY AFTER MIDNIGHT.

A PARTIAL BREAK IN BETWEEN IMPULSES DURING THE EARLY MORNING
HOURS...BUT THE FINAL IMPULSE WILL COMBINE WITH NICE TERRAIN/UPSLOPE
FEATURES FOR SHOWERS TO ONCE AGAIN BLOSSOM BETWEEN 15Z AND 00Z
TOMORROW (EMPHASIS ON LATE MORNING TO AFTERNOON HOURS). SNOW LEVELS
STILL ABOVE 6000 TO 6500 FEET BUT THEY COULD SEE ANOTHER 2-4 INCHES
ABOVE 7000 FEET. BLEND OF ECMWF/NAMDNG5/SREF HAS BEEN HANDLING
TIMING...COVERAGE AND INTENSITIES PRETTY WELL.

RATHER COOL THE NEXT COUPLE OF NIGHTS...ESPECIALLY THURSDAY NIGHT
INTO FRIDAY MORNING...BUT NOTHING EXTREME. PATCHY FOG POSSIBLE THE
NEXT COUPLE OF MORNINGS WITH THE RESIDUAL BOUNDARY LAYER MOISTURE
FROM THE PRECIP AND COOL AIRMASS.

STRONG RIDGE SETTING UP IN THE EASTERN PACIFIC OVER THE NEXT 72
HOURS...PUSHING TOWARD THE WEST COAST OVER THE WEEKEND. STORM TRACK
RECEDES TO HIGHER LATITUDES AS WE SEE DRY CONDITIONS AND A WARMING
TREND EARLY NEXT WEEK. SOME HINTS OF THE FLOW BUCKLING AND ANOTHER
TROUGH IMPACTING MUCH OF THE REGION LATE NEXT WEEK NEAR TO JUST
AFTER CHRISTMAS. WE`LL SEE IF IT CAN DIG DEEP ENOUGH TO BRING WINTER
WEATHER TO OUR NECK OF THE WOODS.

&&

.AVIATION...VALID THRU 19/04Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL
CONTINUE THRU THIS EVENING WITH PERHAPS AN ISOLATED RUMBLE OF
THUNDER. BKN-OVC CLOUDS AT 4-6K FT AGL WITH MULTIPLE BKN-OVC LAYERS
ABOVE. EXPECT LOCAL MVFR CONDITIONS AT GENERALLY 2-3K FT ESP IN THE
VICINITY OF SHOWERS THRU THIS EVE. SFC WINDS DIMINISHING THIS
EVENING...BECOMING DIURNAL AND TERRAIN DRIVEN FROM LATE THIS EVENING
THROUGH TOMORROW AFTERNOON. ANOTHER ROUND OF SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL SPREAD INTO THE AREA BY LATE
THURSDAY MORNING WITH SKY CONDITIONS QUITE SIMILAR TO TODAY.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE THROUGH THURSDAY IN
THE FORM OF VALLEY RAIN AND MOUNTAIN SNOW WITH SOMEWHAT OF A BREAK
IN THE PRECIPITATION TONIGHT. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH ACCUMULATING SNOWS OCCURRING GENERALLY ABOVE 7000 FT AND
SEVERAL INCHES POSSIBLE. BREEZY SOUTHWESTERLY WINDS NEAR THE
INTERNATIONAL BORDER THIS AFTERNOON SHOULD TAPER OFF DURING THE
EARLY EVENING HOURS WITH LIGHTER WESTERLY WINDS OCCURRING THURSDAY.
MOSTLY DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND WITH
PLENTY OF PASSING HIGHER CLOUDS AND FAIRLY LIGHT NORTH TO NORTHWEST
WINDS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY AZZ510-
     511-514 ABOVE 7000 FEET UNTIL 5AM THURSDAY MORNING.

&&

$$

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DISCUSSION...MEYER
AVIATION/FIRE WEATHER...81






000
FXUS65 KTWC 180338
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
845 PM MST WED DEC 17 2014

.SYNOPSIS...AFTER A PARTIAL BREAK IN THE EARLY MORNING HOURS...A LOW
PRESSURE SYSTEM WILL CONTINUE TO BRING PERIODS OF VALLEY RAIN AND
MOUNTAIN SNOW TO THE AREA THROUGH THURSDAY EVENING. SEASONABLY COOL
THE NEXT FEW NIGHTS...OTHERWISE EXPECT DRIER CONDITIONS WITH A
GRADUAL WARMING TREND INTO CHRISTMAS EVE.

&&

.DISCUSSION...SOLID SHOT OF VALLEY RAIN AND MOUNTAIN SNOW THIS
AFTERNOON AND EVENING. WIDESPREAD RAINFALL AMOUNTS IN THE .3 TO .6
OF AN INCH RANGE ACROSS TUCSON METRO. FIRST IMPULSE LAST NIGHT
LOWERED OUR SNOW LEVELS SO THAT ELEVATIONS ABOVE 7500 FEET STARTED
WITH SNOW INSTEAD OF RAIN WITH THIS SECOND STRONGER IMPULSE DURING
THE AFTERNOON HOURS. REPORTS OF 4 TO 5 INCHES OF SNOW AT SUMMERHAVEN
AS OF 4:30 PM JUST BEFORE A SECOND BAND OF MODERATE SHOWERS MOVED
THROUGH THE AREA. STILL SOME LIGHT TO MODERATE ACTIVITY UP THERE AS
OF 830 PM BUT SLOWING CONSIDERABLY FROM WEST TO EAST. CAMERAS ON MT
GRAHAM INDICATED 5 TO 6 INCHES OF SNOW AT AN ADOT YARD RIGHT AT
SUNSET AND THE SNOTEL SENSOR AT HANNAGAN MEADOWS WAS AT 4 INCHES AS
OF 7PM. WE WILL PROBABLY BE ABLE TO CANCEL THE SNOW ADVISORY EARLY
FOR THOSE LOCATIONS...AS WE SHOULD CONTINUE TO SEE A DECREASE IN
COVERAGE AND INTENSITY AFTER MIDNIGHT.

A PARTIAL BREAK IN BETWEEN IMPULSES DURING THE EARLY MORNING
HOURS...BUT THE FINAL IMPULSE WILL COMBINE WITH NICE TERRAIN/UPSLOPE
FEATURES FOR SHOWERS TO ONCE AGAIN BLOSSOM BETWEEN 15Z AND 00Z
TOMORROW (EMPHASIS ON LATE MORNING TO AFTERNOON HOURS). SNOW LEVELS
STILL ABOVE 6000 TO 6500 FEET BUT THEY COULD SEE ANOTHER 2-4 INCHES
ABOVE 7000 FEET. BLEND OF ECMWF/NAMDNG5/SREF HAS BEEN HANDLING
TIMING...COVERAGE AND INTENSITIES PRETTY WELL.

RATHER COOL THE NEXT COUPLE OF NIGHTS...ESPECIALLY THURSDAY NIGHT
INTO FRIDAY MORNING...BUT NOTHING EXTREME. PATCHY FOG POSSIBLE THE
NEXT COUPLE OF MORNINGS WITH THE RESIDUAL BOUNDARY LAYER MOISTURE
FROM THE PRECIP AND COOL AIRMASS.

STRONG RIDGE SETTING UP IN THE EASTERN PACIFIC OVER THE NEXT 72
HOURS...PUSHING TOWARD THE WEST COAST OVER THE WEEKEND. STORM TRACK
RECEDES TO HIGHER LATITUDES AS WE SEE DRY CONDITIONS AND A WARMING
TREND EARLY NEXT WEEK. SOME HINTS OF THE FLOW BUCKLING AND ANOTHER
TROUGH IMPACTING MUCH OF THE REGION LATE NEXT WEEK NEAR TO JUST
AFTER CHRISTMAS. WE`LL SEE IF IT CAN DIG DEEP ENOUGH TO BRING WINTER
WEATHER TO OUR NECK OF THE WOODS.

&&

.AVIATION...VALID THRU 19/04Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL
CONTINUE THRU THIS EVENING WITH PERHAPS AN ISOLATED RUMBLE OF
THUNDER. BKN-OVC CLOUDS AT 4-6K FT AGL WITH MULTIPLE BKN-OVC LAYERS
ABOVE. EXPECT LOCAL MVFR CONDITIONS AT GENERALLY 2-3K FT ESP IN THE
VICINITY OF SHOWERS THRU THIS EVE. SFC WINDS DIMINISHING THIS
EVENING...BECOMING DIURNAL AND TERRAIN DRIVEN FROM LATE THIS EVENING
THROUGH TOMORROW AFTERNOON. ANOTHER ROUND OF SCATTERED VALLEY
RAIN/MOUNTAIN SNOW SHOWERS WILL SPREAD INTO THE AREA BY LATE
THURSDAY MORNING WITH SKY CONDITIONS QUITE SIMILAR TO TODAY.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE THROUGH THURSDAY IN
THE FORM OF VALLEY RAIN AND MOUNTAIN SNOW WITH SOMEWHAT OF A BREAK
IN THE PRECIPITATION TONIGHT. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH ACCUMULATING SNOWS OCCURRING GENERALLY ABOVE 7000 FT AND
SEVERAL INCHES POSSIBLE. BREEZY SOUTHWESTERLY WINDS NEAR THE
INTERNATIONAL BORDER THIS AFTERNOON SHOULD TAPER OFF DURING THE
EARLY EVENING HOURS WITH LIGHTER WESTERLY WINDS OCCURRING THURSDAY.
MOSTLY DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND WITH
PLENTY OF PASSING HIGHER CLOUDS AND FAIRLY LIGHT NORTH TO NORTHWEST
WINDS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY AZZ510-
     511-514 ABOVE 7000 FEET UNTIL 5AM THURSDAY MORNING.

&&

$$

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DISCUSSION...MEYER
AVIATION/FIRE WEATHER...81







000
FXUS65 KTWC 172109
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
209 PM MST WED DEC 17 2014

.SYNOPSIS...TROUGH OF LOW PRESSURE WILL CONTINUE TO BRING VALLEY
RAIN AND MOUNTAIN SNOW TO THE AREA THROUGH TOMORROW NIGHT. THEN
EXPECT DRY CONDITIONS WITH A GRADUAL WARMING TREND INTO CHRISTMAS
EVE.

&&

.DISCUSSION...BEGINNING TO SEE SOME ENHANCEMENT IN PRECIPITATION
THANKS TO AN IMPULSE IN THE FLOW. THE ENERGY WITH THIS IMPULSE
WILL GENERALLY STAY NORTH OF TUCSON...SO BULK OF PRECIPITATION
WILL BE THERE. THAT BEING SAID THERE IS ENOUGH MOISTURE IN PLACE
FOR CONTINUAL OFF AND ON SHOWERS THROUGHOUT THE EVENING.

AFTER THIS IMPULSE MOVES THROUGH THIS EVENING EXPECT TO SEE
ANOTHER LULL IN SHOWERS AFTER MIDNIGHT. THEREFORE...HAVE CONTINUED
THE LOWER POP FROM PREVIOUS PACKAGE...THOUGH HAVE SLIGHTLY
INCREASED POPS ACROSS THE NORTHERN THIRD OF THE FORECAST AREA FOR
THIS PERIOD. THIS IS TO ACCOUNT FOR THE ADDITIONAL MOISTURE EXPECT
NORTH OF TUCSON AND ANY LINGERING ENERGY. HAVE ALSO ADDED SOME FOG
MENTION FOR PINAL COUNTY DURING THIS TIME. NOT EXPECTING MUCH IN
THE WAY OF DENSE OR MAJOR VISIBILITY REDUCTION AS RADIATIVE
COOLING WILL BE LIMITED.

THEN TOMORROW MORNING ANOTHER IMPULSE WILL SLIDE THROUGH THE AREA.
THIS TIME THE BULK OF THE ENERGY WILL BE ACROSS NORTHERN SONORA
MEXICO. THIS WILL KEEP THE BEST QPF VALUES ACROSS THE SOUTHERN
HALF OF THE AREA TOMORROW. AS THIS IMPULSE EXITS THE REGION SO
DOES THE MOISTURE...THOUGH GRADUALLY. BY MIDNIGHT FRIDAY MOST OF
THE SHOWER ACTIVITY WILL BE GONE THOUGH HAVE REINTRODUCED LOW END
SLIGHT CHANCE POPS TO THE HIGHER ELEVATIONS OUT EAST.

FRIDAY THE UPPER RIDGE AXIS SHIFT OVER HEAD ALLOWING FOR THE AREA
TO DRY OUT AND WARM UP. THOUGH...THE WARM UP WILL BE GRADUAL. WITH
THE LOCATION OF THE UPPER HIGH LATE WEEK AND INTO THE WEEKEND
SHOULD KEEP MOSTLY NORTHWEST FLOW IN PLACE. GUIDANCE HAS TRENDED
AWAY FROM THE WEEKEND SHORTWAVE ENERGY HAVING ANY IMPACT ON THE
AREA AS THEY KEEP TRENDING FURTHER EAST WITH IT. THERE IS SOME
INDICATION THAT THE RIDGE MAY BEGIN TO BREAK DOWN OVER THE AREA
AROUND CHRISTMAS AS A PACIFIC TROUGH BEGINS TO DIG ACROSS THE
WESTERN STATES. STAY TUNED.


&&

.AVIATION...VALID THRU 19/00Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL
CONTINUE THRU THIS EVENING WITH PERHAPS AN ISOLATED RUMBLE OF
THUNDER. BKN-OVC CLOUDS AT 4-6K FT AGL WITH MULTIPLE BKN-OVC LAYERS
ABOVE. EXPECT LOCAL MVFR CONDITIONS AT GENERALLY 2-3K FT ESP IN THE
VICINITY OF SHOWERS THRU THIS EVE. SFC WINDS WILL BE GENERALLY
WLY/SWLY AT 8-15 KTS WITH A FEW GUSTS UP TO AROUND 20 KTS POSSIBLE
IN FAR SRN AREAS THIS AFTERNOON. WINDS THEN BECOMING DIURNAL AND
TERRAIN DRIVEN FROM LATE THIS EVENING THROUGH TOMORROW AFTERNOON.
ANOTHER ROUND OF ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL OCCUR THURSDAY WITH SKY CONDITIONS QUITE SIMILAR TO
TODAY. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE THROUGH THURSDAY IN
THE FORM OF VALLEY RAIN AND MOUNTAIN SNOW WITH SOMEWHAT OF A BREAK
IN THE PRECIPITATION TONIGHT. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH ACCUMULATING SNOWS OCCURRING GENERALLY ABOVE 7000 FT AND
SEVERAL INCHES POSSIBLE. BREEZY SOUTHWESTERLY WINDS NEAR THE
INTERNATIONAL BORDER THIS AFTERNOON SHOULD TAPER OFF DURING THE
EARLY EVENING HOURS WITH LIGHTER WESTERLY WINDS OCCURRING THURSDAY.
MOSTLY DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND WITH
PLENTY OF PASSING HIGHER CLOUDS AND FAIRLY LIGHT NORTH TO NORTHWEST
WINDS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS
FIRE WEATHER...81

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000
FXUS65 KTWC 172109
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
209 PM MST WED DEC 17 2014

.SYNOPSIS...TROUGH OF LOW PRESSURE WILL CONTINUE TO BRING VALLEY
RAIN AND MOUNTAIN SNOW TO THE AREA THROUGH TOMORROW NIGHT. THEN
EXPECT DRY CONDITIONS WITH A GRADUAL WARMING TREND INTO CHRISTMAS
EVE.

&&

.DISCUSSION...BEGINNING TO SEE SOME ENHANCEMENT IN PRECIPITATION
THANKS TO AN IMPULSE IN THE FLOW. THE ENERGY WITH THIS IMPULSE
WILL GENERALLY STAY NORTH OF TUCSON...SO BULK OF PRECIPITATION
WILL BE THERE. THAT BEING SAID THERE IS ENOUGH MOISTURE IN PLACE
FOR CONTINUAL OFF AND ON SHOWERS THROUGHOUT THE EVENING.

AFTER THIS IMPULSE MOVES THROUGH THIS EVENING EXPECT TO SEE
ANOTHER LULL IN SHOWERS AFTER MIDNIGHT. THEREFORE...HAVE CONTINUED
THE LOWER POP FROM PREVIOUS PACKAGE...THOUGH HAVE SLIGHTLY
INCREASED POPS ACROSS THE NORTHERN THIRD OF THE FORECAST AREA FOR
THIS PERIOD. THIS IS TO ACCOUNT FOR THE ADDITIONAL MOISTURE EXPECT
NORTH OF TUCSON AND ANY LINGERING ENERGY. HAVE ALSO ADDED SOME FOG
MENTION FOR PINAL COUNTY DURING THIS TIME. NOT EXPECTING MUCH IN
THE WAY OF DENSE OR MAJOR VISIBILITY REDUCTION AS RADIATIVE
COOLING WILL BE LIMITED.

THEN TOMORROW MORNING ANOTHER IMPULSE WILL SLIDE THROUGH THE AREA.
THIS TIME THE BULK OF THE ENERGY WILL BE ACROSS NORTHERN SONORA
MEXICO. THIS WILL KEEP THE BEST QPF VALUES ACROSS THE SOUTHERN
HALF OF THE AREA TOMORROW. AS THIS IMPULSE EXITS THE REGION SO
DOES THE MOISTURE...THOUGH GRADUALLY. BY MIDNIGHT FRIDAY MOST OF
THE SHOWER ACTIVITY WILL BE GONE THOUGH HAVE REINTRODUCED LOW END
SLIGHT CHANCE POPS TO THE HIGHER ELEVATIONS OUT EAST.

FRIDAY THE UPPER RIDGE AXIS SHIFT OVER HEAD ALLOWING FOR THE AREA
TO DRY OUT AND WARM UP. THOUGH...THE WARM UP WILL BE GRADUAL. WITH
THE LOCATION OF THE UPPER HIGH LATE WEEK AND INTO THE WEEKEND
SHOULD KEEP MOSTLY NORTHWEST FLOW IN PLACE. GUIDANCE HAS TRENDED
AWAY FROM THE WEEKEND SHORTWAVE ENERGY HAVING ANY IMPACT ON THE
AREA AS THEY KEEP TRENDING FURTHER EAST WITH IT. THERE IS SOME
INDICATION THAT THE RIDGE MAY BEGIN TO BREAK DOWN OVER THE AREA
AROUND CHRISTMAS AS A PACIFIC TROUGH BEGINS TO DIG ACROSS THE
WESTERN STATES. STAY TUNED.


&&

.AVIATION...VALID THRU 19/00Z.
ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW SHOWERS WILL
CONTINUE THRU THIS EVENING WITH PERHAPS AN ISOLATED RUMBLE OF
THUNDER. BKN-OVC CLOUDS AT 4-6K FT AGL WITH MULTIPLE BKN-OVC LAYERS
ABOVE. EXPECT LOCAL MVFR CONDITIONS AT GENERALLY 2-3K FT ESP IN THE
VICINITY OF SHOWERS THRU THIS EVE. SFC WINDS WILL BE GENERALLY
WLY/SWLY AT 8-15 KTS WITH A FEW GUSTS UP TO AROUND 20 KTS POSSIBLE
IN FAR SRN AREAS THIS AFTERNOON. WINDS THEN BECOMING DIURNAL AND
TERRAIN DRIVEN FROM LATE THIS EVENING THROUGH TOMORROW AFTERNOON.
ANOTHER ROUND OF ISOLATED TO SCATTERED VALLEY RAIN/MOUNTAIN SNOW
SHOWERS WILL OCCUR THURSDAY WITH SKY CONDITIONS QUITE SIMILAR TO
TODAY. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...UNSETTLED WEATHER WILL CONTINUE THROUGH THURSDAY IN
THE FORM OF VALLEY RAIN AND MOUNTAIN SNOW WITH SOMEWHAT OF A BREAK
IN THE PRECIPITATION TONIGHT. SNOW LEVELS WILL BE AS LOW AS 6000 FT
WITH ACCUMULATING SNOWS OCCURRING GENERALLY ABOVE 7000 FT AND
SEVERAL INCHES POSSIBLE. BREEZY SOUTHWESTERLY WINDS NEAR THE
INTERNATIONAL BORDER THIS AFTERNOON SHOULD TAPER OFF DURING THE
EARLY EVENING HOURS WITH LIGHTER WESTERLY WINDS OCCURRING THURSDAY.
MOSTLY DRY CONDITIONS ARE EXPECTED THROUGH THE COMING WEEKEND WITH
PLENTY OF PASSING HIGHER CLOUDS AND FAIRLY LIGHT NORTH TO NORTHWEST
WINDS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

DISCUSSION...MEADOWS
FIRE WEATHER...81

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