Area Forecast Discussion
Issued by NWS Aberdeen, SD

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000
FXUS63 KABR 280205 AAA
AFDABR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
905 PM CDT MON JUL 27 2015

.UPDATE...
ISSUED AT 858 PM CDT MON JUL 27 2015

NO MAJOR UPDATES PLANNED FOR THE FORECAST. GIVEN STRONG/HOT EML
PER MODELS/SOUNDINGS...STILL NOT ENTIRELY SURE ABOUT CONVECTION
IN THE EAST CWA BUT WITH DECENT FRONT EXPECTED TO TRAVERSE THE
CWA TNT WILL KEEP IN HIGH SCT POPS. TEMPERATURES SHOULD BE OK.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 305 PM CDT MON JUL 27 2015

HOT AND HUMID CONDITIONS PERSIST ACROSS THE REGION THIS
AFTERNOON...WITH DEWPOINTS SOLIDLY IN THE 70S ACROSS THE EASTERN
CWA. TEMPERATURES ARE IN THE 90S...AND THE COMBINATION HAS RESULTED
IN ML CAPE VALUES IN THE 4000-5000 J/KG RANGE ACROSS THE EASTERN 2/3
OF THE CWA. LITTLE TO NO CAP IS IN PLACE OVER THE REGION AS
WELL...ALTHOUGH WARMING TEMPERATURES ALOFT IS KEEPING THE WESTERN
THIRD OF THE CWA SUFFICIENTLY CAPPED. 0-6 KM SHEAR IS IN THE 20 TO
30 KTS RANGE AS WELL. IF STORMS COULD INITIATE IN THIS
ENVIRONMENT...DO BELIEVE ISOLATED SEVERE STORMS ARE POSSIBLE. THE
PROBLEM IS FORCING. NO NOTABLE UPPER LEVEL FORCING...SO INITIATION
WILL DEPEND ON LOW LEVEL MOISTURE CONFERENCE...AND THAT REMAINS
QUITE UNCERTAIN AT THIS TIME AS WELL. A FEW HI RES MODELS DO SHOW
ISOLATED STORMS...SO PERSISTED WITH A 20 POP FOR NOW.

TONIGHT...BETTER UPPER LEVEL FORCING AND A COLD FRONT WILL TRACK
ACROSS THE REGION. BULK SHEAR WILL INCREASE AS THE UPPER LEVEL
TROUGH APPROACHES...AND MU CAPE REMAINS QUITE HIGH THROUGH THE
NIGHT. THE BEST CHANCES STILL REMAIN ACROSS NORTH DAKOTA...BUT
SEVERE STORMS ARE POSSIBLE. DUE TO THE STRONG LOW LEVEL WIND
SHEAR...HIGH WINDS MAY BE A CONCERN WITH OVERNIGHT STORMS. STEEP
LAPSE RATES AND HIGH PWATS ALSO SUPPORT THE HAIL AND HEAVY RAIN
THREAT. AT THIS POINT CANNOT RULE OUT AN ISOLATED TORNADO EITHER.

ON THE BACK SIDE OF THIS SYSTEM SUBSIDENCE AND PRIME MIXING
CONDITIONS WILL RESULT IN VERY STRONG AND GUSTY WEST TO NORTHWEST
WINDS TUESDAY. A HIGH WIND WATCH HAS BEEN ISSUED FOR A FEW COUNTIES
ACROSS THE NORTHERN CWA. WINDS THIS STRONG ARE QUITE ANOMALOUS FOR
JULY IN SOUTH DAKOTA. THE AIRMASS WILL BE MUCH LESS HUMID AND HIGH
TEMPERATURES IN THE 70S AND 80S ARE EXPECTED TUESDAY AFTERNOON. DRY
AND RELATIVELY COOLER CONDITIONS PERSIST INTO WEDNESDAY AS WELL.

.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 305 PM CDT MON JUL 27 2015

THERE IS A GENERAL AGREEMENT AMONG MODELS WITH THE EVOLUTION OF THE
UPPER LEVEL FLOW PATTERN THROUGH THE WEEKEND. MOST OF THE PERIOD
WILL FEATURE A WEST TO NORTHWEST FLOW ALOFT WITH DRY AND SEASONAL
CONDITIONS. BY THE WEEKEND...A FEW MODELS ARE SUGGESTING SCATTERED
THUNDERSTORMS POSSIBLE...MAINLY FOR THE EASTERN CWA. LATE
SUNDAY...THE ECMWF SHOWS THE FLOW PATTERN BECOMING ZONAL WITH
COOLER TEMPERATURES AND BETTER CHANCES FOR PCPN. THE GFS ON THE
OTHER HAND SHOWS RIDGING WITH WARMER TEMPERATURES AND DRY
CONDITIONS. WITH LOW CONFIDENCE...WILL RUN WITH GUIDANCE FROM
SUPERBLEND.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 631 PM CDT MON JUL 27 2015

VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THUNDERSTORMS
ARE ALSO POSSIBLE OVERNIGHT...BUT AM NOT CONFIDENT IN
PLACEMENT/MOVEMENT OF THAT ACTIVITY SO WILL LEAVE OUT OF MOST TAFS
FOR NOW.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...HIGH WIND WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR
     SDZ003>005-009-015.

MN...NONE.
&&

$$

UPDATE...TDK
SHORT TERM...SERR
LONG TERM...SD
AVIATION...TDK


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