Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 KOAX 220844
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
344 AM CDT FRI AUG 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 341 AM CDT FRI AUG 22 2014

CONVECTIVE ACTIVITY HAS DEVELOPED OVER SWRN IA AND SERN NEB THIS
MORNING ALONG A SFC TROF EXTENDING FROM NRN IA TO WRN KS. SIMILAR
TO THE LAST SEVERAL NIGHTS...ENVIRONMENT IS QUITE UNSTABLE WITH
MUCAPES AROUND 3000 J/KG WITH A STRONG LLVL MOISTURE FEED INTO THE
PLAINS. EXPECT ACTIVITY WILL GRADUALLY DIMINISH OVER THE NEXT
SEVERAL HOURS AND BE OUT OF THE CWA BY SUNRISE.

MOST PRESSING ISSUE FOR THIS FCST PACKAGE IS POTENTIAL SVR
TSTMS ALONG WITH HEFTY RAINFALL ANTICIPATED LATER TONIGHT.

MODELS HAVE BEEN CONSISTENT LAST SEVERAL RUNS FOCUSING IN ON THE
NRN CWA WITH RESPECT TO HIGH POTENTIAL FOR HEAVY NOCTURNAL PCPN
LATER TONIGHT. AN OPEN GULF WITH PERSISTENT MOISTURE ADV THRU
TODAY WILL ENSURE A MOISTURE RICH ENVIRONMENT WILL BE IN PLACE
DURING THE OVERNIGHT HOURS.

TODAY...MODELS PROG A POTENT LITTLE VORT MAX EJECTING OUT OF THE
BASE OF A DEEP UPPER TROF SITUATED OVER THE WRN CONUS WITH DPVA
INDUCING LEESIDE CYCLOGENESIS INVOF THE CNTRL HIGH PLAINS. MODELS
AGREE SFC LOW WILL RAPIDLY LIFT TWD THE DAKOTAS THIS AFTN ALONG
WITH ATTENDANT WARM FRONT PUSHING INTO THE CWA LATE THIS AFTN.
COMBINATION OF STOUT INSTABILITY/EFF SHEAR AND ADEQUATE DEEP LYR
SHEAR WITH PROVIDE A FAVORABLE ENVIRONMENT FOR LATE AFTN/EARLY
EVENING SUPERCELL DEVELOPMENT. IN ADDITION...VERY HEAVY
RAINFALL...MAINLY OVER THE NRN CWA...LOOKS VERY PROBABLE TONIGHT
GIVEN COMBINATION OF WARM CLOUD DEPTH AROUND 4500 METERS/SYNOPTIC
SCALE MAX OMEGA WILL BE IN PHASE WITH PWS GREATER THAN 2". BEST
MOISTURE/FORCING THEN QUICKLY LIFTS NORTH OF THE CWA EARLY SAT
MORNING.

SAT NIGHT AND SUN...MODELS PROG A SOMEWHAT STRONG COLD FRONT
APPROACHING THE CWA. NOT ALL THAT IMPRESSED WITH PCPN POTENTIAL SO
WILL OPT FOR TOKEN 20S DURING THOSE PDS.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 341 AM CDT FRI AUG 22 2014

COMPARED TO 21/00Z RUN...LATEST ECM IS NOW TRYING TO COME BACK IN
LINE WITH GFS/CMC SOLUTIONS SWEEPING A CANADIAN AIR MASS INTO THE
NRN/CNTRL PLAINS LATER NEXT WEEK WITH PCPN CHANCES FOCUSED ON
FRONTAL BNDRY PASSAGE. GOING POPS LOOK REASONABLE THUS NO MAJOR
CHANGES PLANNED.

&&

.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1136 PM CDT THU AUG 21 2014

ISOLATED TO SCATTERED TSRA HAVE DEVELOPED THIS EVENING AND STILL
COULD AFFECT THE KLNK/KOMA TAFS FOR THE NEXT COUPLE OF HOURS
BEFORE THE ACTIVITY SHIFTS EWD AND OUT OF THE TAF SITES. NOT
EXPECTING HEAVY TSRA...BUT BRIEF MVFR CONDS WOULD BE POSSIBLE.
OTHERWISE WE MAY SEE SOME MVFR FG TOWARD MRNG AT KOMA/KOFK. VFR
CONDS ARE EXPECTED THROUGH THE DAY ON FRI...BUT BY THE END OF THE
PERIOD SOME TSRA ARE POSSIBLE AT KOFK AND WILL INCLUDE A TEMPO
GROUP AFTER 03Z WITH MVFR CONDS. SOME THREAT AT KOMA/KLNK AS WELL
BUT CURRENTLY CONFIDENCE IS HIGHER AT KOFK.


&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$

SHORT TERM...DEE
LONG TERM...DEE
AVIATION...



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