National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KABR 131742 AAC
AFDABR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
1242 PM CDT MON MAY 13 2013

.UPDATE...

UPDATED AVIATION DISCUSSION BELOW FOR 18Z TAFS.

NO MAJOR CHANGES PLANNED TO THE CURRENT FORECAST. INCREASED CLOUD
COVER THIS MORNING BASED ON MOVEMENT OF A PRETTY DENSE CIRRUS
SHIELD SHOWN ON SATELLITE. EXPECT THESE CLOUDS TO THIN OUT A BIT
IN THE AFTERNOON. CLOUDS ARE NOT EXPECTED TO IMPACT THE HIGH TEMP
FORECAST TODAY.


&&

.PREVIOUS DISCUSSION...

.SHORT TERM...TODAY THROUGH WEDNESDAY
FIRE WEATHER WILL REMAIN THE PRIMARY FOCUS...SEE FIRE WEATHER
DISCUSSION FOR GREATER DETAIL.

MID LEVEL CLOUD COVER WITH SCATTERED RETURNS THIS AM. WITH A 20 TO
25 DEGREE DEWPOINT DEPRESSION...THINKING THESE ARE ALL VIRGA.
A TROF AXIS HAS STARTED TO PUSH EAST OUT OF WYOMING THIS AM. H85
TEMPERATURES TO THE WEST OF THIS FEATURE ARE SOME 10 TO 15 DEGREES
CELSIUS WARMER...SO WILL CONTINUE TO ADVERTISE WELL ABOVE AVERAGE
TEMPERATURES THANKS TO FAVORABLE MIXING DIRECTION. REGIONAL
DEWPOINTS RANGE FROM MID 20S OVERHEAD...TO MID 40S TO THE SOUTH
AND NORTHWEST. BOTH OF THESE AREAS OF HIGHER HUMIDITY WILL PUSH
INTO THE REGION...HOWEVER GUIDANCE CONTINUES TO BE ENTIRELY TOO
BULLISH ON THE REGIONAL DEWPOINTS...WHICH SHOULD HAVE NO PROBLEM
MIXING OUT DURING THE DAY.

NEXT FEATURE TO HONE IN ON IS A WEAK AREA OF LOW PRESSURE. H85
TEMPERATURES TOP OUT AROUND +26C TUESDAY MORNING AHEAD OF THIS
FEATURE...WHICH WILL HELP ENHANCE THE THERMAL GRADIENT AND THUS
MIXING WINDS TUESDAY AM...WITH H85 TEMPERATURES DROPPING TO +15C
BY MID DAY. SUSPECT SOME LOCATIONS WILL SEE HIGH TEMPERATURES WITH
MIXING IN THE AM...AND TEMPERATURES FALLING/STEADY THROUGH THE
AFTERNOON. COLD ADVECTION WILL BE MET WITH DRY AIR ADVECTION SO
FIRE WEATHER WILL REMAIN A CONCERN. WINDS MAY ALSO PEAK IN THE AM
AS STRONGEST MID LEVEL WINDS MIX OUT EARLY...WITH WIND MAXIMUM
MOVING EAST THROUGH THE DAY. MIXED DOWN WINDS TOP OUT IN THE 40 TO
50KT RANGE WITH SOME OF THE HIGHER GUIDANCE.


.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
SURFACE HIGH PRESSURE AND A WEAK UPPER LEVEL RIDGE WILL SLIDE
ACROSS THE REGION WEDNESDAY NIGHT. SEVERAL SHOTS OF ENERGY WILL
THEN RIDE UP THE EASTERN SIDE OF AN APPROACHING UPPER TROUGH
THURSDAY THROUGH EARLY SATURDAY BEFORE THE TROUGH REACHES THE
PLAINS. SATURDAY THROUGH THE DAY SUNDAY...THE UPPER TROUGH MOVES
PRETTY SLOWLY...ONLY REACHING NORTHERN WISCONSIN BY THE END OF THE
PERIOD...AND KEEPING DECENT ENERGY OVER THE NORTHERN PLAINS. THE
SURFACE LOW REACHES THE WESTERN PLAINS THURSDAY/THURSDAY
NIGHT...WITH PRECIPITATION DEVELOPING AHEAD OF IT. CANNOT RULE OUT
ANY PERIOD FROM THEN THROUGH THE END OF THE PERIOD WHEN IT WILL BE
DRY...SO GENERALLY STUCK WITH ALLBLEND POPS. LOOKS TO BE DECENT
INSTABILITY BOTH FRIDAY NIGHT AND SATURDAY AFTERNOON/EVENING...WHICH
MAY RESULT IN THE POTENTIAL FOR SOME STRONG TO SEVERE
THUNDERSTORMS DURING THOSE TIME PERIODS.

HIGH TEMPERATURES IN THE 70S WILL BE COMMON THURSDAY THROUGH
SATURDAY. SLIGHTLY COOLER AIR WILL MOVE IN ON THE BACK SIDE OF
THE LOW PRESSURE SYSTEM...RESULTING IN HIGHS ONLY IN THE 60S ON
SUNDAY.


&&

.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

VFR CONDITIONS WILL PERSIST THROUGH THE TAF FORECAST PERIOD WITH
JUST SOME PASSING HIGH LEVEL CLOUDS.


&&

.FIRE WEATHER...
RED FLAG CONDITIONS EXPECTED FOR MUCH OF THE CWA TODAY. SOUTH
WINDS WILL BEGIN TO MIX INTO THE 20 TO 30 MPH RANGE BY LATE
MORNING...WITH A WIND SHIFT ALSO EXPECTED. THE WIND SHIFT WILL BE
ACCOMPANIED BY A SURGE IN MUCH WARMER AIR. MAIN QUESTION WILL BE
AFTERNOON HUMIDITY. MODEL DEWPOINTS SURGE INTO THE UPPER 40S/LOW
50S...HOWEVER REGIONAL DEWPOINTS ARE IN THE MID 40S AT BEST
CASE...AND I WOULD EXPECT THESE WILL DROP LOWER WITH MIXING.
THEREFORE...MINIMUM AFTERNOON RH VALUES WILL LIKELY TOP 10 TO 20
PERCENT.

WINDS GO BACK TO SOUTH AND ARE EXPECTED TO SLACKEN A LITTLE THIS
EVENING AND DURING THE EARLY OVERNIGHT HOURS...HOWEVER A COLD
FRONT WILL PUSH RAPIDLY ACROSS THE DAKOTAS DURING THE
MORNING HOURS. WHILE AFTERNOON HUMIDITY IS EXPECTED TO SEE MODEST
IMPROVEMENT...20 TO 30 PERCENT...WINDS WILL INTENSIFY
SIGNIFICANTLY...WITH GUSTS UPWARDS OF 50 MPH.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...RED FLAG WARNING UNTIL 8 PM CDT /7 PM MDT/ THIS EVENING FOR
     LOWER BAD RIVER-MISSOURI COTEAU-PRAIRIE COTEAU-RED RIVER
     VALLEY-UPPER CHEYENNE-UPPER JAMES RIVER-UPPER MISSOURI
     COTEAU.

     FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
     EVENING FOR LOWER BAD RIVER-MISSOURI COTEAU-PRAIRIE COTEAU-
     RED RIVER VALLEY-UPPER CHEYENNE-UPPER JAMES RIVER-UPPER
     MISSOURI COTEAU.

MN...FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY
     EVENING FOR BIG STONE-TRAVERSE.

&&

$$
UPDATE...WISE/TMT
SHORT TERM...CONNELLY
LONG TERM...PARKIN
AVIATION...TMT
FIRE WEATHER...CONNELLY

WEATHER.GOV/ABERDEEN