043
FXUS63 KABR 241514 AAB
AFDABR
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
1014 AM CDT THU APR 24 2025
KEY MESSAGES
- AREAS OF LIGHT TO MODERATE SHOWERS MOVING ACROSS THE REGION
TODAY/TONIGHT, WITH MOST LOCATIONS GETTING LESS THAN ONE HALF
OF AN INCH OF RAINFALL.
- THE NEXT CHANCE OF RAIN (60 TO 85%) WILL BE FOR THE SECOND HALF
OF THE UPCOMING WEEKEND INTO EARLY NEXT WEEK. THERE IS A 15%
CHANCE FOR SEVERE STORMS EAST OF THE JAMES RIVER MONDAY.
UPDATE
ISSUED AT 1011 AM CDT THU APR 24 2025
SEEING AN AREA OF RAINFALL PUSH NORTHEASTWARD ACROSS THE AREA THIS
MORNING, WITH MUCH OF IT BEING LIGHT. SOME HEAVIER PRECIPITATION
WILL OCCUR ACROSS SOUTHERN PARTS OF THE CWA. STILL LOOKS LIKE WE
WILL SEE A SECONDARY AREA OF RAIN MOVE IN FROM THE WEST LATER THIS
AFTERNOON AND THIS EVENING, WITH THE HIGHEST AMOUNTS LIKELY TO
OCCUR ACROSS CENTRAL SOUTH DAKOTA BEFORE THE PRECIPITATION BECOMES
LIGHT AND SPOTTY AS IT MOVES EAST. NO CHANGES MADE TO WINDS OR
TEMPERATURES AT THIS TIME.
SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/
ISSUED AT 412 AM CDT THU APR 24 2025
SCATTERED LIGHT SHOWERS CONTINUE MOVING NORTHEAST ACROSS
CENTRAL/SOUTH CENTRAL SD, BUT COVERAGE HAS BEEN SOMEWHAT LIMITED
STILL. MORE WIDESPREAD COVERAGE IS NOTED ON RADAR ACROSS WESTERN,
SOUTHERN/SOUTHEAST SD. ALTHOUGH, HI-RES MODELS DO SHOW AN UPTICK IN
COVERAGE ACROSS THE WESTERN CWA OVER THE NEXT SEVERAL HOURS AS
ACTIVITY ACROSS SOUTHWEST/SOUTH CENTRAL SD MOVES NORTHEAST. LATEST
QPF GUIDANCE SUGGESTS PRECIP MAXIMA ACROSS SOUTHEAST SD AND ANOTHER
ONE ACROSS WESTERN SD, WITH OUR CWA IN SOMEWHAT OF A LULL BETWEEN
TWO SOURCES FOR SHOWERS. SOUTHEAST SD MAY BE IN THE BETTER LOCATION
FOR PRECIP BEING IN CLOSER PROXIMITY TO THE SURFACE BOUNDARY ACROSS
THE CENTRAL PLAINS. FURTHER WEST, ANOTHER QPF BULLSEYE OVER WESTERN
SD, LIKELY ASSOCIATED WITH LIFT FROM THE APPROACHING MID-LEVEL WAVE
MOVING INTO THE ROCKIES OUT OF ID/NV. THIS MID-LEVEL FEATURE SEEMS
TO WASH OUT AS IT MOVES EAST THROUGH THE ROCKIES, BUT MAY SEE SOME
DEGREE OF AREAL COVERAGE OF SHOWERS LATER THIS AFTERNOON INTO
EVENING. STILL SEEING VARYING AMOUNTS OF SHOWER COVERAGE AMONGST THE
HI-RES MODELS, WITH PERHAPS A DECREASE IN OVERALL RAINFALL AMOUNTS.
FOR TODAY/TONIGHT, MOST AREAS LIKELY GETTING LESS THAN A HALF INCH,
AND EVEN LESS THAN THAT (LESS THAN 0.25IN) OVER NORTHEAST SD INTO
WEST CENTRAL MN, WHERE OVERALL COVERAGE OF SHOWERS IS REALLY IN
QUESTION THROUGHOUT THIS EVENT.
SURFACE HIGH PRESSURE WILL ESTABLISH ITSELF OVER THE AREA TONIGHT
AND THROUGH THE DAY FRIDAY, WITH CONDITIONS DRYING OUT. HREF CLOUD
COVER ENSEMBLE MEAN, ALONG WITH BUFKIT SOUNDINGS, SUGGEST THERE MAY
BE SOME LOWER LEVEL CLOUD COVER FRIDAY MORNING THAT EVENTUALLY BURNS
OFF AS THE DAY PROGRESSES WHILE THE HIGH IS BUILDING IN. CURRENT SKY
COVER GRIDS REFLECT THIS SCENARIO. HIGH TEMPERATURES ON FRIDAY LOOK
TO BE NEAR NORMAL FOR THIS TIME OF YEAR, WITH HIGHS IN THE LOW TO
MID 60S.
LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/
ISSUED AT 412 AM CDT THU APR 24 2025
CLUSTERS ARE IN AGREEMENT ON THE LONGWAVE TROUGH, AND ITS MID LEVEL
CLOSED LOW, COMING ONSHORE SATURDAY AND MAKING ITS TRACK
EAST/NORTHEAST AND OVER THE ROCKIES THROUGH SUNDAY. THE TROUGH THEN
SPLITS, AS THE NORTHERN SHORTWAVE WILL THEN SHIFT NORTHEAST AND OVER
THE NORTHERN PLAINS MONDAY INTO MONDAY EVENING. THE SOUTHERN
STREAM'S TROUGH WILL TRACK SLOWER AND OVER THE SOUTHWESTERN US BY
00Z TUESDAY. BY TUESDAY MORNING, THIS FASTER NORTHERN WAVE WILL
CONTINUE TO SHIFT EAST, WITH MUCH OF THE CWA ON THE BACKSIDE OF THE
WAVE THROUGH THE DAY WITH THE SOUTHERN WAVE PUSHING EAST AND
BECOMING WEAKER BY MIDWEEK OVER THE CENTRAL TO SOUTHERN CONUS.
BEYOND THIS TIME, A RIDGE LOOKS TO SET UP OVER THE PACIFIC, SHIFTING
EASTWARD THROUGH THE END OF THE NEXT WEEK. WITH THIS PATTERN, WINDS
WILL BE ZONAL FRIDAY AND SATURDAY AND THEN SHIFTING OUT OF THE
SOUTHWEST SATURDAY NIGHT THROUGH MONDAY THEN SHIFTING NORTHWEST
BEHIND THE WAVE TUESDAY. DOWN AT THE SURFACE, A LARGE AREA OF HIGH
PRESSURE WILL BE DOMINANT WITH THE CENTER OF THE HIGH OVER THE GREAT
LAKES BY 12Z SATURDAY. THE EASTERN CWA WILL BE UNDER THE INFLUENCE
OF THIS HIGH AS A PRESSURE GRADIENT STEEPENS OVER THE AREA BETWEEN
THIS HIGH AND THE FORMING SURFACE LOW TO THE WEST. JUMPING AHEAD TO
00Z MONDAY, BOTH ENS/GEFS HAVE A GOOD HANDLE ON THE LEE LOW CENTERED
OVER THE WESTERN DAKOTAS AND SOUTHWARD, WITH THE CENTER OF THE 998MB
LOW CENTERED OVER CENTRAL SD BY 12Z MONDAY. IT THEN TRACKS EAST THEN
NORTHEAST AND OVER THE GREAT LAKES BY 12Z TUESDAY.
GFS IVT CONTINUES TO INDICATE A SURGE OF MOISTURE AS WE WILL BE
CONNECTED TO THE GULF WITH RETURN FLOW AHEAD OF THE SURFACE LOW
SUNDAY AND MONDAY. NAEFS STILL INDICATES MEAN SPECIFIC HUMIDITY
BETWEEN 3 TO 3.5 STANDARD DEVIATIONS ABOVE CLIMO AND PWAT 2 TO 2.5
ABOVE STANDARD DEVIATIONS BETWEEN 12Z SUNDAY AND 18Z MONDAY. THIS
MOISTURE WILL LEAD TO DEWPOINTS INCREASING INTO THE 50S SUNDAY
(HIGHEST IN THE MID 50S OVER CENTRAL SD) THROUGH MONDAY WITH
DEWPOINTS EVEN POSSIBLY RISING INTO THE LOWER 60S OVER THE FAR
EASTERN CWA MONDAY AFTERNOON. STRONG WAA WILL ALLOW TEMPS TO TOP OUT
INTO THE 70S TO EVEN THE LOWER 80S, AROUND AND WEST OF THE MO RIVER
SUNDAY AFTERNOON (10-20 DEGREES ABOVE AVERAGE). AS THE LOW TRACK
EAST SO WILL THE WAA WITH TEMPS MONDAY IN THE UPPER 70S TO LOWER 80S
OVER THE EASTERN HALF OF THE CWA (15-20 DEGREES ABOVE AVERAGE). EFI
INDICATES VALUES OF 0.6 TO 0.9 WITH A SOT OF ZERO FOR THESE AREAS
BOTH DAYS MEANING EC MEMBERS ARE SHIFTING AWAY FROM REFORECAST CLIMO
AND INDICATING THIS IS WARMER THAN AVERAGE BUT NOTHING ANOMALOUS.
COOLER AIR AND LOWER DEWPOINTS MOVE IN BEHIND THE SYSTEM FROM WEST
TO EAST MONDAY NIGHT AND TUESDAY.
AHEAD OF THE LOW, WITH THE WARM FRONT, SLIGHT CHANCES OF POPS ARE
POSSIBLE SATURDAY THROUGH EARLY SUNDAY (15-25%) WITH POPS INCREASING
WEST TO EAST AS THE LOW TRACKS ACROSS THE STATE THROUGH MONDAY. THE
HIGHEST POPS OF 70-85% WILL BE BETWEEN 00Z MONDAY THROUGH 00Z
TUESDAY IN WHICH THE BULK OF THE RAINFALL WILL OCCUR. POPS WILL
DECREASE WEST TO TO EAST MONDAY NIGHT INTO TUESDAY AS THE LOW SHIFTS
NORTHEAST WITH OVERALL DRY CONDITIONS BY TUESDAY AFTERNOON. NBM
PROBABILITY OF 48HR RAINFALL>0.50" ENDING 12Z TUESDAY IS 50-75%,
HIGHEST OVER NORTHEASTERN SD. PROB OF 1" IS 25-55% AGAIN HIGHEST
OVER THE JAMES RIVER VALLEY AND EASTWARD MONDAY EVENING INTO
TUESDAY. NORTHERN AND NORTHEASTERN SD INTO WEST CENTRAL MN HAVE BEEN
HIGHLIGHTED IN A MARGINAL RISK (5%) FOR EXCESSIVE RAINFALL BOTH
SUNDAY AND MONDAY. EC EFI INDICATES THIS WELL FOR QPF WITH VALUES OF
0.5 TO 0.8 AND A SOT OF ZERO OVER THIS AREA FOR MONDAY MEANING EC
MEMBERS INDICATE THIS IS STRAYING AWAY FROM CLIMO BUT NOTHING TOO
ANOMALOUS.
WE ARE STILL WATCHING THE POTENTIAL FOR SEVERE WEATHER WITH THIS
SYSTEM AS PROBABILITY OF CAPE>500 J/KG AND SHEAR>30KTS IS 40-65%,
HIGHEST OVER CENTRAL SD SUNDAY AFTERNOON. EC EFI INDICATES CAPE IS
ABOUT 0.5 TO 0.9 AND A SOT OF ZERO, MAINLY WEST OF THE JAMES RIVER,
HIGHEST OVER CENTRAL SD WITH CAPE-SHEAR UP TO 0.8 AND SOT OF ZERO
OVER NORTH CENTRAL SD. WITH THE WARM MOIST AIR, INSTABILITY, AND
LIFT THIS LOOKS TO BE A SLAM DUNK FOR SEVERE, HOWEVER, ENS STILL
HINTS AT A LARGE CAP (-100+ J/KG) OVER MUCH OF THE AREA SUNDAY
AFTERNOON AND DECREASING JUST A BIT TOWARDS THE EVENING, SO THAT MAY
PUT A DAMPER ON CONVECTION. CIPS ML INDICATES A 10% CHANCE OF SEVERE
WEATHER OVER CENTRAL SD, WITH CSU HAVING A 15-30% CHANCE EXTENDING
OVER CENTRAL SD BUT FURTHER EASTWARD TO THE JAMES RIVER, AND NSSL ML
UP TO A 30% CHANCE. SO THIS WILL BE SOMETHING TO WATCH. MONDAY
AFTERNOON A SOUTHWEST TO NORTHEAST ORIENTED JET STREAK WILL BE
POSITIONED ON THE PVA SIDE OF THE TROUGH WITH SPEEDS OF 40-50KTS
EAST OF THE JAMES RIVER AND WITHIN THE LEFT EXIT REGION, PROVIDING
UL DIVERGENCE NEEDED FOR CONVECTION. ADD IN THE DAYTIME INSTABILITY
(PROB OF CAPE>500 AND SHEAR>30 KTS IS 40-50%) AGAIN WITH THE ONGOING
LOW LEVEL MOISTURE, AND MODELS INDICATING NO CAP, WE HAVE A BETTER
CHANCE FOR SEVERE OVER THE FAR EASTERN HALF OF THE STATE WITH THE
JAMES RIVER BEING THE CUTOFF THE FURTHER WEST YOU GO. HOWEVER THE
EASTERN CWA WILL BE ON JUST THE WEST/NORTHWESTERN FRINGE OF THIS
RISK GIVING THE PLACEMENT OF THE LOW AND FORCING BY THIS TIME WITH
THE GREATER THREAT OVER SOUTHEASTERN SD INTO MN. CIPS KEEPS THE
THREAT OUT OF THE CWA WHILE CSU/SPC INDICATE A 15% RISK OVER FAR
EASTERN SD INTO WESTERN MN. SPC STILL HIGHLIGHTS A 15% CHANCE OVER
FAR EASTERN SD INTO MN. MESOSCALE DETAILS REMAIN SOMEWHAT UNCERTAIN
GIVEN WE ARE STILL SEVERAL DAYS OUT, SO MORE FINE TUNING EXPECTED IN
THE UPCOMING DAYS.
AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
ISSUED AT 643 AM CDT THU APR 24 2025
TERMINALS KABR,KATY,KPIR,KMBG
VFR CIGS ARE STILL IN PLACE TO START OFF THE TAF PERIOD, BUT
EXPECT GRADUALLY LOWERING CLOUDS ACROSS THE REGION TODAY INTO THIS
EVENING INTO MVFR OR EVEN IFR (POTENTIALLY). SIGNS POINT TO KPIR
HAVING THE BEST CHANCE FOR IFR CIGS DURING THE TAF PERIOD. AREAS
OF -SHRA/SHRA WILL MOVE NORTHEAST ACROSS THE REGION TODAY INTO
THIS EVENING, WITH MVFR VSBY AT TIMES.
ABR WATCHES/WARNINGS/ADVISORIES
SD...NONE.
MN...NONE.
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...MMM
AVIATION...TMT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page