Area Forecast Discussion
Issued by NWS Aberdeen, SD

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KABR 300841
AFDABR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
341 AM CDT TUE SEP 30 2014

.SHORT TERM...TODAY THROUGH THURSDAY
A POWERFUL SURFACE LOW PRESSURE SYSTEM CURRENTLY OVER THE
PANHANDLE OF NEBRASKA WILL IMPACT THIS CWA THROUGH LATE THIS
AFTERNOON. THIS DEEPENING LOW PRESSURE SYSTEM WILL BRING STRONG
WINDS TO MOST OF THE CWA...WITH THE HIGHEST SUSTAINED WINDS
OCCURRING OVER CENTRAL SOUTH DAKOTA. BUFFER SOUNDING AT KPIR
INDICATE SUSTAINED WINDS AROUND 20-25 KNOTS...WITH A PEAK GUST OF
45 KNOTS. THUS A WIND ADVISORY HAS BEEN ISSUED FOR CENTRAL SD.

THE PREVIOUS FORECAST WAS WORRIED ABOUT THE EXTENT OF CLOUD COVER
THIS AFTERNOON POTENTIALLY LIMITING SEVERE WEATHER. THE CURRENT
WATER VAPOR IMAGERY SUGGEST THERE WILL BE BREAKS IN THE CLOUDS
TODAY. ONE UPPER LEVEL SHORT WAVE IS WRAPPING INTO THE LOW PRESSURE
SYSTEM WITH A NOTICEABLE DRY SLOT OVER WESTERN NEBRASKA. A
SECONDARY SHORT WAVE CURRENTLY OVER SOUTHERN COLORADO SHOULD
ROTATE INTO CENTRAL SOUTH DAKOTA LATER TODAY. BREAKS IN THE CLOUD
COVER WILL ALLOW FOR DESTABILIZATION TO OCCUR WITHIN A NARROW
CORRIDOR OF WEAK INSTABILITY BUT EXCELLENT SHEAR TO RESULT IN LOW
TOPPED SUPERCELLS. 0-1 KM BULK SHEAR VALUES EXCEEDING 30 KNOTS AND
0-1 KM ENERGY HELICITY INDEX OVER 2 SUGGEST TORNADOES WILL BE
POSSIBLE. THUS WILL MENTION SEVERE IN THE EASTERN HALF OF THE CWA
FOR THIS AFTERNOON.

THIS SYSTEM SHOULD PUSH NORTH OF THE CWA LATER THIS EVENING WITH
MOSTLY DRY CONDITIONS EXPECTED UNTIL THURSDAY. AN UPPER LEVEL
TROUGH MOVING ACROSS THE REGION ON THURSDAY WILL HAVE THE
POTENTIAL TO BRING SHOWERS TO THE EASTERN CWA DURING THE
AFTERNOON HOURS.

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
MEDIUM RANGE MODELS ARE INDICATING A LONGWAVE TROUGH TO PUSH
THROUGH THE NORTHERN PLAINS THURSDAY NIGHT. THE ECWMF IS THE MUCH
STRONGER MODEL WITH WINDS AND MUCH MORE ROBUST WITH ANY PRECIP.
HOWEVER...THE GFS AND CANADIAN ARE MUCH DRIER. WILL RAMP UP WINDS
FOR FRIDAY AND LEAVE POPS AS IS...BUT PRECIP CHANCES WILL HAVE TO
BE RAMPED UP ON FUTURE SHIFTS IF MODELS COME AROUND TO WET ECWMF.
COOL AIRMASS ON SATURDAY WILL BRING A CHANCE OF FROST TO MOST OF
THE AREA...SPLY ALONG AND EAST OF THE JAMES RIVER VALLEY.
NORTHWEST FLOW WILL CONTINUE THROUGH THE WEEKEND WITH WARMER AIR
RETURNING SATURDAY AFTERNOON THROUGH MONDAY. ANY FAST MOVING
SHORTWAVES LOOK TO BE ON THE WEAK SIDE ATTM.

&&

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

AN AREA OF LOW PRESSURE WILL MOVE OVER WESTERN SD TUESDAY. BANDS
OF SHOWERS/TSTORMS WILL WRAP AROUND THE LOW AND MAY AFFECT THE TAF
SITES INTERMITTENTLY. HI-RES MODELS KEEP THE PRECIP VERY SPOTTY
AND HAVE SIGNIFICANTLY SLOWED DOWN ANY EASTWARD PROGRESSION.
THEREFORE HAVE REMOVED MENTION OF VCTS FOR NOW AS CONFIDENCE IS
TOO LOW IN TIMING AND AREAL COVERAGE. SOUTHEAST WINDS ARE STILL
EXPECTED TO INCREASE TO 20 TO 30 KTS ACROSS THE WEST TONIGHT AND
ACROSS THE EAST DURING THE MORNING. WINDS WILL SHIFT TO THE
SOUTHWEST AT KMBG/KPIR TUESDAY EVENING. PRIMARILY VFR CIGS ACROSS
THE REGION WILL DETERIORATE TO MVFR BETWEEN 7Z AND 10Z. CIGS WILL
FLUCTUATE ON TUESDAY BETWEEN MVFR AND VFR.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 7 PM CDT /6 PM
     MDT/ THIS EVENING FOR HUGHES-JONES-LYMAN-STANLEY-SULLY.

MN...NONE.
&&

$$
SHORT TERM...SD
LONG TERM...SCARLETT
AVIATION...SCARLETT

WEATHER.GOV/ABERDEEN



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.