Severe Thunderstorm Warning 227, NWS Bismarck, ND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
300 PM CDT FRI AUG 24 2001

CD FNT ACRS WRN ND WL MV EWD THRU CWA THIS EVENING AND ERLY TNT.
LATEST MSAS AND SFC OBS SHW FNT E OF ISN TO JUST WEST OF DIK INTO
EXTRM SWRN ND. PROBLEMS WI FCST COVER THE POTENTIAL FOR TSTMS.

ETA/AVN RUNS THIS AM WERE CLOSE ON HANDLING THIS FNT WI THE ETA
JUST A BIT FASTER THAN THE AVN. THE DIFFERENCE BEING THAT THE ETA
BUILDS IN THE SFC HIGH INTO THE REGION FASTER THAN THE AVN. THIS
SEEMS TO BE THE CASE THIS SUMMER. I FAVOR AN AVN SOLN TO THE FCST.
BOTH MODELS SHW A BETTER RH FIELD IN THE ERN PART OF THE STATE THAN
IN THE CNTRL AREAS. LOOKING AT LATEST VIS SAT PICS THERE IS
SOME CLD DVLPMT ACRS THE NCNTRL AREA ATTM WI BETTER DYNAMICS AND
RH IN SERN SASK INTO SRN MANITOBA WI ONGOING CONVECTION. AS THE FNT
CONTINUES TO MV EWD I AM TIMING THE FROPA THRU MOT BY 17Z...BIS BY
00Z AND JMS BY 04Z. DUE TO SHARP NATURE OF CD FNT AND WSHIFT I
BELIEVE ANY CHC OF TSTMS WL BE CONFINED ALONG THE FNT...ESP IN THE
NCNTRL AND ECNTRL AREAS. THIS AMS SOUNDING SHWD CAPES OF 1573 J/KG
AND A LI OF -4 IN BIS. MODEL CAPES SHW THIS FIELD SHIFTING EAST WI
THE FNT AND BETTER POTENTIAL FOR TSTMS IN NE AND ERN ND TNT. MODEL
LIS WERE PROGGED TO INC TO -5 IN CNTRL ND AHEAD OF FNT THIS
EVENING...THUS THE CHC OF TSTMS. CURRENT SUNNY SKIES WERE HEATING
THE ATMOSPHERE NICELY AND WL AID THE DESTABILIZATION INTO THE
EVENING. MY PRESENT THINKING IS TO PUT 30 POPS IN MOT AND 20 POPS IN
BIS WI 30 POPS IN JMS AREA FOR THIS EVENING. THEN WI FROPA SKIES
WL CLEAR OUT TNT AS NRN ROCKIES HIGH PRESSURE SYSTEM BUILDS IN
GRADUALLY INTO SAT. SKIES WL BE SUNNY IN MOST AREAS ON SAT WI
BASICALLY CLEAR CONDITIONS SAT NIGHT. SUNDAY THE SFC HIGH MVS
EAST AND SOUTH WINDS DVLP WI SOME RETURN MOIST. NXT FEATURE
APRS TO BE A WK FNT OR TROF MVG IN THE FLOW ACRS ND LATER SUNDAY.
WITH MOISTURE PROGGED TO BE WEAK...I AM LEANING TOWARDS A DRY
FROPA WI A FEW CLDS POSSIBLE THEN. AS FAR AS TEMPS GO...PREVIOUS
MAX/MIN FCST SEEMS REASONABLE AND IN LINE WI NEW MODEL GUIDANCE
THROUGH THE WEEKEND AND ONLY MADE MINOR ADJUSTMENTS.

IN THE LONGER TERM...CURRENT LARGE UPPER HIGH WHICH COVERS MUCH
OF SRN US IS PROGGED TO RELOCATE TO THE SW US BY MID NXT WEEK
WHICH WL ALLOW FOR L/W TROF TO DVLP OVR ERN US THEN. THIS LOOKS
TO BE A PATTERN CHANGE AND WL LEAD TO NW FLOW AND COOLER TEMPS
FOR THE MIDDLE OF NXT WEEK. CHCS OF PCPN LOOK TO BE SMALL AND
CONFINED TO TUESDAY AND WEDNESDAY AND THUS CHANGED THIS WORDING
IN THE EXTENDED.

.BIS...NONE.
JENSEN