FXUS63 KOAX 101747
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1247 PM CDT TUE MAY 10 2011
.DISCUSSION...
HAVE MADE A FEW TWEAKS TO THE FORECAST TODAY AND ANTICIPATE A FEW
MORE TO THE EVENING FORECAST LATER THIS AFTERNOON. FRONT-ISH
FEATURE AT 17Z WAS DIFFUSE...EXTENDING FROM SURFACE LOW IN
NORTHEAST SD THROUGH AROUND KNOX CO TO PLATTE CO TO JEFFERSON
CO...AND THEN SOUTHWESTWARD TOWARD THE OK PANHANDLE. WESTERNMOST
CWA REMAINS ON THE COOL SIDE OF THAT BOUNDARY...AND HAVE LOWERED
HIGHS IN THE WEST /SUBSTANTIALLY SO IN THE NORTHWEST/. NUDGED
HIGHS DOWNWARD EVERYWHERE WITH MORE MOISTURE LINGERING TODAY THAN
YESTERDAY...AND EXPECT HIGHS TO BE A FEW DEGREES COOLER THAN
YESTERDAY EVEN ON THE WARM SIDE OF THE FRONT.
SOME CONCERN ABOUT THUNDERSTORMS THIS EVENING...BUT SUSPICIOUS IF
COVERAGE WILL REACH HIGH-CHANCE RANGE. DO BELIEVE THAT SHEAR WILL
BE TOO LOW TO SUPPORT SEVERE CONVECTION...AND DO LIKE THE 00Z/12Z 4
KM WRF DEPICTION OF EVENING CONVECTION THAT MAINLY DIES AWAY
OVERNIGHT...RATHER THAN NAM DEPICTION THAT HOLDS PRECIP THROUGH
THE NIGHT AND INTO WEDNESDAY MORNING. SREF SUPPORT FOR PRECIP
THROUGH THE NIGHT IS WEAK AS WELL...ADDING SUPPORT TO A LESS WET
OVERNIGHT.
UPDATED GRIDS/ZFP ALREADY SENT.
&&
.PREV DISCUSSION... /ISSUED 301 AM CDT TUE MAY 10 2011/
DISCUSSION...TODAY THROUGH THURSDAY NIGHT.
FEATURE OF CONCERN THIS MORNING WAS LARGE UPPER LEVEL LOW PRESSURE
OVER THE GREAT BASIN THIS MORNING PER WV IMAGERY. MEANWHILE DEEP SFC
LOW WAS CENTERED OVER THE NEB/SD BORDER WITH ATTENDANT WARM FRONT
THRU NERN NEB INTO NRN IA...WITH A THERMAL BNDRY/DRY LINE EXTENDING
SOUTH FROM NEB PANHANDLE THRU WRN KS TO TX PANHANDLE. CONVECTIVE
COMPLEX IN WRN SD LIFTING INTO ND ASSOCIATED WITH STRONG LFQ
DIVG/WAA.
HAVE DECIDED TO INTRODUCE POPS THIS EVENING GIVEN LATEST NSSL/NCEP
4KM HIRES PROGS SHOWING AREA OF CONVECTION DEVELOPING THIS EVENING
WITHIN AREA OF UNCAPPED AIR. UNLIKE PREVIOUS RUNS...NAM/GFS SOLUTIONS
NOW COMPLIMENTING HIRES PROGS PLACING QPF IN CWA. OTHERWISE MODEL
CONSISTENCY PRETTY GOOD SHOWING GREAT BASIN LOW SEGMENTING AS IT
PUSHES EAST WITH NRN PIECE OF ENERGY LIFTING THRU THE WRN DAKOTAS
THIS AFTN THEN INTO CANADA BY WED AFTN. MEANWHILE SRN ENERGY
PROGGED TO EXIT THE 4 CORNERS REGION THIS MORNING AND BECOME THE
INFLUENCING FEATURE FOR CONVECTION WED AFTN INTO THURSDAY OVER THE
CNTRL PLAINS. FOR THE MOST PART HAVE USED BLEND OF NAM/GFS BNDRY LYR
MOISTURE CONVG LINE AS A GUIDE FOR PLACEMENT OF POPS GIVEN ABUNDANT
MOISTURE/INSTABILITY UNTIL AT LEAST EARLY THURSDAY MORNING. APPEARS
THAT THIS SYSTEM WILL BE SLOW TO MOVE EAST DUE TO IT REMAINING JUST
NORTH OF THE SUBTROPICAL JET.
AS FOR TEMPS...MIXING THIS AFTN COULD BE AS DEEP AS IT WAS ON MONDAY
AND APPEARS TO BE GOOD POTENTIAL RECORDS MIGHT BE SET AGAIN. STANDING
RECORD HIGHS FOR TODAY...OFK 89/OMA 93/LNK 93. COOLING TREND THEN ON
TAP HEADING INTO THIS WEEKEND WITH HIGHS FRIDAY AND SATURDAY ONLY IN
THE MID 60S.
DEE
AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
POTENTIAL FOR LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH ABOUT 14Z
AND SOME MVFR VISIBILITIES MAY OCCUR ESPECIALLY AT KOMA AND KLNK.
COLD FRONT CURRENTLY TO THE WEST OF THE TAF SITES WILL MOVE EAST
TODAY AND BE OVER EASTERN NEBRASKA BY LATE AFTERNOON. IT APPEARS
THAT THUNDERSTORM CHANCES WILL INCREASE BY EARLY EVENING...BUT FOR
NOW CHANCES APPEAR LOW ENOUGH TO NOT INCLUDE THUNDERSTORM MENTION
IN TAFS. WILL TAKE ANOTHER LOOK AT THAT WITH 12Z ISSUANCE.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
MAYES