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000
FXUS01 KWBC 260815
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
415 AM EDT THU MAY 26 2016

VALID 12Z THU MAY 26 2016 - 12Z SAT MAY 28 2016

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE
SOUTHERN/CENTRAL PLAINS INTO PARTS OF THE MIDDLE/LOWER MISSISSIPPI
VALLEY...

...HEAVY RAIN POSSIBLE OVER PARTS OF THE LOWER/MIDDLE MISSISSIPPI
VALLEY AND THE CENTRAL/SOUTHERN PLAINS...

A DEEP UPPER-LEVEL TROUGH EXTENDING FROM THE NORTHERN HIGH PLAINS
TO THE SOUTHWEST WILL SLOWLY MOVE EASTWARD TO THE PLAINS BY FRIDAY
EVENING.  DIURNAL HEATING WILL AID IN PRODUCING SHOWERS AND
THUNDERSTORMS OVER THE NORTHERN INTERMOUNTAIN REGION SOUTHWARD TO
THE GREAT BASIN/SOUTHWEST EASTWARD TO THE NORTHERN/CENTRAL HIGH
PLAINS ON THURSDAY/FRIDAY AFTERNOON AND EVENING.  THE AREAL
COVERAGE OF THE SHOWERS AND THUNDERSTORMS WILL BE AT A MINIMUM
DURING THE LATE NIGHT AND MORNING TIME PERIODS.

DOWNSTREAM FROM THE UPPER-LEVEL TROUGH, MOISTURE FROM THE GULF OF
MEXICO WILL MOVE NORTHWARD OVER THE SOUTHERN PLAINS/LOWER
MISSISSIPPI VALLEY INTO THE GREAT LAKES/OHIO VALLEY AND INTO THE
UPPER MISSISSIPPI VALLEY THAT WILL CONTINUE THROUGH FRIDAY
EVENING.  SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER PARTS OF THE
PLAINS AND MISSISSIPPI VALLEY INTO THE GREAT LAKES AND OHIO VALLEY
THROUGH FRIDAY EVENING.  AN AREA OF SHOWERS AND THUNDERSTORMS WILL
DEVELOP OVER THE OHIO VALLEY ON LATE THURSDAY MORNING INTO
AFTERNOON THAT WILL MOVE INTO THE NORTHERN/CENTRAL APPALACHIANS
AND THE MID-ATLANTIC BY THURSDAY EVENING THEN DISSIPATE.  ON
FRIDAY THE SHOWERS AND THUNDERSTORMS WILL REDEVELOP OVER THE
NORTHERN/CENTRAL APPALACHIANS AND EXPAND INTO PARTS OF THE
NORTHEAST AND INTO PARTS OF THE SOUTHERN APPALACHIANS BY FRIDAY
EVENING.  IN ADDITION, A FRONT WILL DEVELOP OVER THE PACIFIC
NORTHWEST BY THURSDAY EVENING MOVING EASTWARD TO THE NORTHERN
ROCKIES/GREAT BASIN BY FRIDAY EVENING.  RAIN WILL DEVELOP OVER
PARTS OF THE PACIFIC NORTHWEST COAST ON THURSDAY EXPANDING INTO
PARTS OF THE NORTHERN INTERMOUNTAIN REGION BY FRIDAY EVENING.


ZIEGENFELDER


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_WBG.PHP
$$







000
FXSA20 KWBC 251517
PMDSA

SOUTH AMERICA FORECAST DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1117 AM EDT WED MAY 25 2016

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

MODEL DISCUSSION (VALID FROM MAY 25 AT 0000 UTC): CONFIDENCE IN
THE FORECAST REMAINS HIGH THROUGH 120 HRS...WITH GLOBAL MODELS AND
ENSEMBLE MEMBERS FOLLOWING A SIMILAR EVOLUTION.

MID LEVEL FLOW ACROSS THE EASTERN PACIFIC SPLITS BETWEEN A RIDGE
ON THE SOUTHERN STREAM AND A TROUGH TO THE NORTH. THE RIDGE IS TO
INITIALLY ANCHOR ON A CLOSED HIGH OVER TIERRA DEL FUEGO...THAT
MOVES TO THE MALVINAS/FALKLAND ISLANDS BY 54/60 HRS. BY 72-96 HRS
IT IS TO SETTLE ALONG 50W TO THE WEDDELL SEA/ANTARCTIC
PENINSULA...WHERE IT IS TO THEN HOLD THROUGH THE END OF THE CYCLE.
AT LOW LEVELS THIS WILL ANCHOR A RIDGE OVER PATAGONIA/WESTERN
ATLANTIC THROUGH 48-60 HRS. THIS...IN-TURN...WILL SUSTAIN A MOIST
EASTERLY FLOW ACROSS LA PAMPA TO NORTHERN PATAGONIA. AS THE
PARCELLS ADIABATICALLY LIFT...THIS IS TO THEN FAVOR GENERATION OF
SCATTERED CONVECTION ALONG THE EASTERN SLOPES OF THE ANDES ACROSS
NORTHERN PATAGONIA. IN THIS AREA WE NOW EXPECT MAXIMA OF
15-20MM...WITH MODELS PROJECTING LOCALLY HIGHER AMOUNTS DUE TO
STRONG TOPOGRAPHICAL FORCING.

THE MID LEVEL TROUGH TO THE NORTH...MEANWHILE...IS TO MEANDER OVER
SOUTHERN-CENTRAL CHILE THROUGH 36-48 HRS...THEN SLOWLY PULL ACROSS
THE ANDES INTO ARGENTINA BY 48-60 HRS. AS IT PULLS ACROSS
ARGENTINA TO PARAGUAY THIS WILL SUSTAIN FRONTOGENESIS...WITH
BOUNDARY TO GRADUALLY STRENGTHEN THROUGH 84-96 HRS. AS IT BECOMES
BETTER ORGANIZED THIS WILL TRIGGER MODERATE CONVECTION WITH
ACCUMULATION OF 20-45MM/DAY...TO AFFECT PARAGUAY BY 48-60 HRS AND
MATO GROSSO DO SUL-SOUTHERN BRASIL BY 72 HRS. BY 96-108 HRS
CONVECTION WILL INCREASE TO 25-50MM/DAY WITH LOCALLY HIGHER
AMOUNTS HIGHLY LIKELY.

FURTHERMORE...UNDER THE INFLUENCE OF THE SOUTHERN STREAM RIDGE...A
POLAR TROUGH IN THE SOUTHERN STREAM FLOW CONTINUES TO AMPLIFY
ACROSS THE SOUTH ATLANTIC. THROUGH 48-60 HRS THE TROUGH IS TO
REACH MAXIMUM AMPLITUDE AS IT IS TO EXTEND BETWEEN 50W-00W AND TO
THE SOUTH OF 30S. AT LOW LEVELS THIS WILL SUSTAIN A FRONT ACROSS
NORTHERN PATAGONIA/LA PAMPA IN ARGENTINA. THIS IS TO MEANDER NORTH
ACROSS THE BUENOS AIRES PROVINCE TO RIO DE LA PLATA BASIN BY 48
HRS...AND NORTH INTO URUGUAY/ENTRE RIOS IN ARGENTINA BY 72 HRS.
THIS IS TO THEN INTERACT WITH DEEPENING TROUGH OVER
PARAGUAY/SOUTHERN BRASIL. AS IT MEANDERS NORTH...THE FRONT WILL
TRIGGER COASTAL CONVECTION WITH ACCUMULATION OF 00-05MM/DAY.

ANOTHER FRONT LIES TO THE NORTH...WITH AXIS WEST-NORTHWEST ACROSS
ESPIRITO SANTO-MINAS GERAIS. THE FRONT SUSTAINS A PREFRONTAL SHEAR
LINE ACROSS EASTERN BAHIA...WHERE IT IS TO REMAIN OVER THE NEXT
FEW DAYS. THIS WILL BE THE FOCUS OF LOW LEVEL MOISTURE
CONVERGENCE...WITH MODELS PROJECTING MODERATE AMOUNTS OVER THE
NEXT FEW DAYS WITH DAILY MAXIMA PEAKING AROUND 15-30MM. THROUGH 96
HRS THIS IS TO DECREASE TO 10-15MM/DAY.

AT 200 HPA...A RIDGE BUILDS OVER THE EASTERN TROPICAL PACIFIC
THROUGH 48-72 HRS. AS THE RIDGE INTENSIFIES IT IS TO THEN SUSTAIN
THE NORTHWARD AMPLIFICATION OF A TROUGH ACROSS THE PERUVIAN JUNGLE
TO SOUTHERN COLOMBIA. THE AMPLIFYING TROUGH IS TO THEN FAVOR AN
INCREASE IN DIURNAL CONVECTION ACROSS AMAZONAS IN BRASIL...SRN
COLOMBIA AND NORTHERN PERU...WHERE THE MAXIMA PEAKS AT 20-30MM BY
60-108 HRS. OTHERWISE...LIGHT TO MODERATE CONVECTION IS TO BUILD
ACROSS NORTHERN BRASIL IN A DIURNAL PATTERN THAT WILL SUSTAIN
RAINFALL AMOUNTS OF 10-15MM/DAY.

ENRIQUEZ...DGAC (ECUADOR)
AYALA...DINAC (PARAGUAY)
DAVISON...WPC (USA)

$$







000
FXSA20 KWBC 251332
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
931 AM EDT WED MAY 25 2016

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

SYNOPSIS (VALID FROM MAY 25 AT 0000 UTC): A 200 HPA NORTHERN
HEMISPHERE LOW CENTERS OVER SOUTHERN ECUADOR...ANCHORING A SHORT
WAVE TROUGH OVER THE EASTERN TROPICAL PACIFIC. THE TROUGH ALOFT IS
ENHANCING CONVECTION ACROSS EQUATORIAL SOUTH AMERICA...WITH MOST
INTENSE CLUSTERING OVER COLOMBIA-NORTHWEST BRASIL-EASTERN ECUADOR.

AT 250 HPA...THE SOUTHERN POLAR HAS ITS ENTRANCE AT 35S
112W...THEN ALONG A 139KT MAXIMUM AT 41S 108W...46S 107W...58S
107W...A 163KT MAXIMUM AT 67S 100W...71S 81W...A 146KT MAXIMUM AT
68W 56W...61S 54W...EXITING AT 54S 56W. THE JET REFORMS AT 51S
55W...THEN ALONG 48S 45W...47S 36W...EXITING AT 46S 28W. AN
ANTICYCLONICALLY CURVED BRANCH OF THE NORTHERN POLAR HAS ITS
ENTRANCE AT 52S 92W...THEN ALONG 58S 94W...65S 85W...65S 72W...59S
65W...EXITING AT 49S 70W. THE JET REFORMS AT 38S 89W...CROSSING
36S 83W...36S 77W...38S 69W...41S 59W...40S 49W...EXITING AT 36S
43W. A FINGER OF THE SUBTROPICAL LIES BETWEEN 31S 84W AND 31S 69W.
ANOTHER BRANCH TO THE NORTH HAS ITS ENTRANCE AT 19S 98W...THEN
ALONG 21S 91W...22S 83W...EXITING AT 20S 74W. THE JET REFORMS AT
20S 35W...THEN ALONG 26S 25W...30S 16W...EXITING AT 35S 09W.

AT 500 HPA...THE FLOW OVER THE EASTERN PACIFIC DIVIDES BETWEEN A
RIDGE AND A TROUGH. THE RIDGE EXTENDS FROM A CLOSED HIGH AT 53S
81W TO THE ANTARCTIC PENINSULA/BELLINGSHAUSEN SEA...WHILE THE
TROUGH TO THE NORTH BOUNDS BETWEEN 90W-70W AND TO THE SOUTH OF
26S. THE TROUGH ANCHORS ON A CLOSED LOW NEAR 41S 80W. AN INDUCED
RIDGE TO THE EAST EXTENDS ACROSS SOUTHERN BRASIL TO PARAGUAY. OVER
THE ATLANTIC...AN AMPLIFYING TROUGH EXTENDS ALONG 60S 30W...54S
40W...TO 50S 65W. ANOTHER TROUGH TO THE NORTH...MEANWHILE...LIES
ALONG 40S 25W...30S 40W...TO SOUTHEAST BRASIL.

AT LOW LEVELS...IN A SPLIT FLOW PATTERN...A RIDGE ON THE SOUTHERN
STREAM ANCHORS ON TWO 1029 HPA HIGHS...WITH ONE AT 55S 78W AND THE
OTHER AT 54S 70W. A TROUGH TO THE NORTH...MEANWHILE...ANCHORS ON A
1008 HPA LOW AT 39S 77W...WITH A WANING FRONT THAT EXTENDS ALONG A
1016 HPA LOW AT 39S 73W...35S 75W...A 1014 HPA LOW AT 33S
77W...31S 83W...TO 32S 92W. THIS FAVORS SCATTERED CONVECTION
BETWEEN PUERTO MONTT AND CONCEPCION IN CHILE. FARTHER EAST...A 978
HPA LOW AT 55S 29W EXTENDS A FRONT ALONG A 982 HPA LOW AT 55S
23W...49S 25W...46S 38W...A 1010 HPA LOW AT 46S 46W...45S 57W...TO
SOUTHERN PATAGONIA IN ARGENTINA. FARTHER NORTH...AN OCCLUDED 998
HPA LOW AT 38S 16W EXTENDS A FRONT ALONG A 1002 HPA LOW AT 41S
09W...36S 10W...A 1008 HPA LOW AT 35S 16W...29S 20W...A 1018 HPA
LOW AT 24S 28W...18S 35W...TO TOCANTINS/GOIAS IN BRASIL. A
PREFRONTAL SHEAR LINE EXTENDS FROM THIS BOUNDARY TO EASTERN BAHIA
WHERE IT FAVORS SCATTERED DEEP CONVECTION. SOUTH OF THE FRONT...A
RIDGE ANCHORS ON A 1029 HPA HIGH AT 33S 46W.

AYALA...DINAC (PARAGUAY)
ENRIQUEZ...DGAC (ECUADOR)
DAVISON/GALVEZ...WPC (USA)
$$







000
FXUS01 KWBC 250815
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
415 AM EDT WED MAY 25 2016

VALID 12Z WED MAY 25 2016 - 12Z FRI MAY 27 2016

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
SOUTHERN PLAINS TO THE UPPER/MIDDLE MISSISSIPPI VALLEY AND PARTS
OF THE CENTRAL/NORTHERN PLAINS...

...HEAVY RAIN POSSIBLE OVER PARTS OF THE SOUTHERN PLAINS...

...HEAVY RAIN POSSIBLE OVER PARTS OF THE CENTRAL PLAINS/MIDDLE
MISSISSIPPI VALLEY...

A DEEP UPPER-LEVEL TROUGH OVER THE WESTERN THIRD OF THE COUNTRY
WILL MOVE EASTWARD TO THE PLAINS/ROCKIES BY THURSDAY EVENING.
UNDER THE UPPER-LEVEL TROUGH, SHOWERS AND THUNDERSTORMS WILL
DEVELOP FROM PARTS OF CALIFORNIA TO THE NORTHERN INTERMOUNTAIN
REGION/GREAT BASIN AND THE NORTHERN/CENTRAL ROCKIES BY WEDNESDAY
EVENING WITH DAYTIME HEATING CONTRIBUTING TO THE AREAL EXTEND OF
THE STORMS.  ON THURSDAY, THE SHOWERS AND THUNDERSTORMS WILL
EXTEND FROM THE NORTHERN/CENTRAL HIGH PLAINS TO THE GREAT
BASIN/NORTHERN INTERMOUNTAIN REGION WITH DAYTIME HEATING
CONTRIBUTING TO THE AREAL EXTEND.

DOWNSTREAM FROM THE UPPER-LEVEL TROUGH, MOISTURE FROM THE GULF OF
MEXICO WILL STREAM NORTHWARD OVER THE SOUTHERN PLAINS INTO THE
MIDDLE MISSISSIPPI VALLEY AND THE UPPER MIDWEST THAT WILL EXTEND
INTO THE GREAT LAKES/OHIO VALLEY BY THURSDAY EVENING.  SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER PARTS OF THE PLAINS AND THE
MISSISSIPPI VALLEY THAT WILL EXPAND INTO PARTS OF THE GREAT
LAKES/OHIO VALLEY BY WEDNESDAY EVENING.  BY THURSDAY MORNING, THE
SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER PARTS OF THE UPPER
MISSISSIPPI VALLEY/UPPER GREAT LAKES SOUTHWESTWARD INTO THE
SOUTHERN PLAINS AND OVER THE GREAT LAKES/OHIO VALLEY WILL EXPAND
EASTWARD INTO PARTS OF THE NORTHERN/CENTRAL APPALACHIANS BY
THURSDAY EVENING.

IN ADDITION ON THURSDAY, A FRONT WILL DEVELOP OVER THE PACIFIC
NORTHWEST AND MOVE EASTWARD TO THE NORTHERN INTERMOUNTAIN REGION
BY THURSDAY EVENING AS UPPER-LEVEL ENERGY MOVES ONSHORE OVER THE
NORTHWEST.  RAIN WILL DEVELOP OVER PARTS OF THE PACIFIC NORTHWEST
COAST ON THURSDAY AS THE ENERGY MOVES INLAND.


ZIEGENFELDER


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_WBG.PHP
$$







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