FXUS63 KOAX 041951
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
251 PM CDT THU AUG 4 2011
.SHORT TERM...TONIGHT.
MID LEVEL CIRCULATION WORKING ITS WAY ACROSS SOUTHEAST NEBRASKA THIS
AFTERNOON SHOULD BE EXITING THE FORECAST AREA THIS EVENING. PLENTY
OF MOISTURE BUT INSTABILITY HAS REMAINED LIMITED. WILL KEEP LOW POPS
FOR THIS EVENING ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA
COUNTIES. MODELS CONTINUE TO SHOW ANOTHER VERY WEAK WAVE MOVING INTO
THE REGION TONIGHT. WILL LOWER POPS IN THE EAST AFTER MIDNIGHT AND
EXTEND CHANCES A BIT FURTHER NORTH IN THE WEST...BUT CANNOT SEE
GOING ABOVE 20 TO 30 PERCENT ANYWHERE OVER THROUGH THE OVERNIGHT
PERIOD WITH ONLY WEAK UPPER SUPPORT AND LITTLE INSTABILITY.
.LONG TERM...FRIDAY THROUGH THURSDAY.
INCREASED TO CHANCE POPS FRIDAY DUE TO WAVY ZONAL FLOW AND
LINGERING INSTABILITY. LATEST NAM BUFR SOUNDINGS INDICATE STEEP
LOW LEVEL LAPSE RATES AND SUFFICIENT MOISTURE FOR CONVECTION DURING
THE DAY FRIDAY. ALTHOUGH THERE REMAINS SOME UNCERTAINTY IN
COVERAGE AND TIMING OF ANY STORMS FRI...BEST CHC WILL BE AFTER
16S AS SOUNDINGS REACH THEIR CONVECTIVE TEMPS AND SHUD BE ABLE TO
TAP INTO 1500 J/KJ CAPE. THE STORMS ARE NOT EXPECTED TO BECOME
SEVERE DUE TO A LACK OF SHEAR. HOWEVER...HEAVY RAIN WILL BE
POSSIBLE AS PWAT VALUES HANG ON AROUND 2 INCHES.
FOCUS TURNS TO A DEEPENING H85 LOW THAT TRACKS EAST OVER THE
DAKOTAS...SWEEPING A WEAK COLD FRONT/H85 TROUGH ACROSS THE REGION
SATURDAY AFTERNOON/EVENING. KEPT CHC POPS FOR THE FROPA DURING THE
SAT/SAT NIGHT PERIOD. A FEW OF THE STORMS WILL HAVE THE POTENTIAL
TO BECOME SEVERE...MAINLY AFTER 22Z SATURDAY.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
VFR CONDITIONS TO CONTINUE THROUGH AROUND 09Z AT KOFK...WITH MVFR
CEILINGS AND VISIBILITIES DEVELOPING AFTER. CANNOT RULE OUT A BRIEF
PERIOD OF IFR CONDITIONS SOMETIME BETWEEN 09Z AND 14Z. CONDITIONS
SHOULD IMPROVE TO VFR AFTER 14Z. FOR KOMA AND KLNK...MIXED MVFR/VFR
CEILINGS INITIALLY WILL IMPROVE TO VFR BY 20Z-21Z. MVFR CEILINGS AND
VISIBILITIES SHOULD REDEVELOP AFTER 09Z...LASTING THROUGH AROUND
15Z. CANNOT RULE OUT A BRIEF PERIOD OF IFR CONDITIONS SOMETIME
BETWEEN 09Z AND 14Z AT KOMA AND KLNK AS WELL.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
GRANING/SENA