000
FXUS63 KABR 210840
AFDABR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
340 AM CDT TUE MAY 21 2013

.SHORT TERM...TODAY THROUGH THURSDAY
THE UPPER LEVEL CLOSED LOW CONTINUES TO ROTATE OVER SOUTH
DAKOTA. WATER VAPOR SATELLITE IMAGERY SHOWS A VERY
DISTINGUISHABLE WAVE OF ENERGY THAT IS ROTATING AROUND THE
BACKSIDE OF THE LOW. THE RESULT IS CONTINUED LIGHT RAIN SHOWERS
ALONG AND NORTH OF I90 IN OUR CWA. THE UPPER LOW WILL VERY SLOWLY
SHIFT SOUTHEAST TODAY...HOWEVER IT WILL NOT GET TOO FAR...WITH THE
UPPER LOW CENTER SOMEWHERE AROUND THE SD/IA/MN BORDERS BY THE END
OF THE DAY. THEREFORE...EXPECT CONTINUED LIGHT RAIN SHOWERS
ACROSS THE REGION THROUGHOUT THE DAY. WHILE PRETTY UNLIKELY...CAN
NOT COMPLETELY RULE OUT A RUMBLE OF THUNDER ACROSS THE NORTHEAST
CWA WITH WEAK ML CAPE VALUES IN PLACE. A TIGHT SURFACE PRESSURE
GRADIENT WILL ALSO SET UP ON THE BACK SIDE OF THE SURFACE
LOW...ALLOWING FOR GUSTY NORTHERLY WINDS ACROSS THE WESTERN AND
CENTRAL CWA THIS AFTERNOON. WITH ABUNDANT CLOUD COVER AND COLD AIR
ADVECTION...TEMPERATURES WILL LIKELY BE STEADY OR SLOWLY FALLING
THIS AFTERNOON...WITH MAX TEMPS TOPPING OUT SOMEWHERE IN THE 50S.

THE LOW PRESSURE SYSTEM WILL FINALLY WORK ITS WAY SOUTHEAST OF
THE REGION ON WEDNESDAY. THERE WILL LIKELY BE LINGERING RAIN
SHOWERS ACROSS THE EAST IN THE MORNING...BUT SHOULD GRADUALLY
TAPER OFF THROUGH THE AFTERNOON HOURS. AFTERNOON TEMPERATURES
WILL BE TRICKY ON WEDNESDAY SINCE THEY WILL BE HIGHLY DEPENDENT ON
HOW QUICKLY CLOUD COVER BEGINS TO BREAK APART.

BY LATE WEDNESDAY AND THURSDAY MORNING A HIGH PRESSURE RIDGE WILL
BE DRAPED ACROSS THE REGION. THIS FEATURE WILL QUICKLY MOVE
EASTWARD ALLOWING FOR RETURN FLOW WINDS AND WARM AIR TO ADVECT
BACK INTO THE REGION THURSDAY AFTERNOON...ALONG WITH THE
BEGINNINGS OF ANOTHER SURGE OF GULF MOISTURE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY
AN UPPER RIDGE OF HIGH PRESSURE OVER THE PLAINS WILL BEGIN TO
MOVE EAST THURSDAY NIGHT AND FRIDAY. AT THE SFC MODELS HAVE BEEN
FAIRLY CONSISTENT DEVELOPING A LEE SIDE TROF THU NIGHT AND FRI
WITH A 35 KT LLJ OVER MUCH OF THE REGION FRIDAY. THIS WILL BE THE
FOCUS POINT FOR SOME TSTORMS BY LATE FRI AFTERNOON. THIS LATE DAY
INSTABILITY WILL REMAIN THROUGH THE WEEKEND. AS A WEAK LOW
TRANSITIONS OFF THE ROCKIES SHOWER CHANCES WILL REMAIN IN THE
PICTURE THROUGH THE START OF THE NEXT WORK WEEK. TEMPERATURES WILL
BEGIN TO CLIMB CLOSER TO AVERAGE WITH THE SOUTHERLY FLOW...THOUGH
ABUNDANT MOISTURE AND SOME EXPECTED CLOUD COVER WILL TOP THEM OUT
IN THE MID 70S SUN THROUGH TUESDAY.

&&

.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

AN AREA OF RAIN WILL CONTINUE TO SPIN OVER MUCH OF CENTRAL AND
NORTHEASTERN SOUTH DAKOTA OVERNIGHT AND THROUGH THE DAY TUESDAY.
CIGS AND VSBYS WILL VARY BETWEEN VFR AND MVFR LEVELS WITH THE
RAINFALL. BREEZY NORTHERLY WINDS OF 20 TO 30 MPH WILL AFFECT KPIR
AND KMBG.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
SHORT TERM...SERR
LONG TERM...WISE
AVIATION...WISE

WEATHER.GOV/ABERDEEN