FXUS63 KOAX 082031
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
331 PM CDT MON AUG 8 2011
.SHORT TERM...TONIGHT
THERE REMAINS AN AREA OF LOW PRESSURE ALOFT STRADDLING THE SOUTH
DAKOTA/NEBRASKA BORDER...SLOWLY MOVING SOUTHEAST. WEAK ELEVATED
ACCAS SHOWERS/THUNDERSTORMS HAVE BEEN ASSOCIATED WITH THIS UPPER
WAVE ALL DAY. HARD TO TELL IF SURFACE-BASED STORMS WILL BE ABLE TO
GET GOING LATE THIS AFTERNOON THROUGH LATE THIS EVENING UNDERNEATH
THE MID-LEVEL LIFT ASSOCIATED WITH THIS WEAK SYSTEM. LAPS ANALYSIS
AND AVAILABLE SHORT TERM MODEL GUIDANCE SUGGESTS THERE MAY BE ENOUGH
INSTABILITY/SHEAR AROUND FOR AN ISOLATED STRONG TO SEVERE STORM...SO
KEPT SOME LOW POPS GOING THIS AFTERNOON INTO THIS EVENING...BUT
BECOMING LESS CONFIDENT IN PRECIPITATION DEVELOPING/MOVING OVER THIS
CWA. DROPPED POPS/WX MENTION ALTOGETHER FROM 06Z TO 12Z TUESDAY. AS
FOR TEMPERATURES...FAIRLY DRY LOW LEVEL AIR IS ADVECTING INTO THE
CWA NOTED BY DEWPOINTS IN THE LOW TO MID 60S THROUGHOUT MUCH OF THE
CWA. DRIER AIR AND LIGHT WINDS UNDER A PARTLY CLOUDY TO MOSTLY CLEAR
SKY SHOULD HELP TEMPERATURES TO FALL TO NEAR 60 DEGREES ACROSS THE
NORTHERN ZONES TO MID 60S ACROSS THE SOUTHERN ZONES.
&&
.LONG TERM...TUESDAY THROUGH MONDAY
HIGH PRESSURE WILL QUICKLY MOVE IN BEHIND FRONTAL PASSAGE...WITH DRY
CONDITIONS RETURNING TO THE REGION. IT WILL NOT LAST LONG...AS THE
HIGH WILL MOVE EAST AND BRING RETURN FLOW/ISENTROPIC ASCENT ACROSS
WESTERN NEBRASKA. A SHORTWAVE WILL INTERACT WITH THIS MOISTURE
TUESDAY AFTERNOON/EVENING...WITH AN MCS LIKELY TO FORM DURING THE
EVENING/OVERNIGHT HOURS. THE QUESTION REMAINS PLACEMENT OF THE LOW
LEVEL JET...AND THUS THE PATH OF THE THUNDERSTORM COMPLEX. HAVE
CONTINUED WITH PREVIOUS THINKING THAT MUCH OF THE ACTIVITY WILL
REMAIN ACROSS CENTRAL NEBRASKA...WITH A CHANCE OF THUNDER ACROSS OUR
NEBRASKA ZONES. WHERE THIS COMPLEX SETS UP WILL ALSO DETERMINE
RAINFALL AMOUNTS...AND HEAVY RAINFALL IS POSSIBLE JUST WEST OF OAX
CWA.
MODELS ARE HINTING AT A SECOND SHORTWAVE DEVELOPING CONVECTION
DURING THE DAY WEDNESDAY...AND HAVE CHANCE POPS FOR THE WEST AND
SOUTHERN ZONES...AND WILL CONTINUE TO FINE TUNE AS MORE DATA BECOMES
AVAILABLE.
UNSETTLED PATTERN WILL REMAIN UNTIL COLD FRONT MOVES THROUGH
FRIDAY...ALTHOUGH RAIN CHANCES WILL REMAIN SMALL. HIGH PRESSURE WILL
THEN BRING A RETURN TO A DRY FORECAST FOR THE WEEKEND.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
SKIES ARE COMPLETELY CLEAR...AND VSBYS ARE UNRESTRICTED. LOOKS
LIKE ONLY SOME WEAK VIRGA SHOWERS OF RAIN STARTING TO EEK INTO THE
FAR NWRN CORNER OF THE CWA. KOFK COULD STILL SEE A BRIEF RAIN SHOWER
LATE THIS AFTERNOON. BUT...OVERALL...ALL THREE TERMINALS ARE LIKELY
TO EXPERIENCE SOME GOOD VFR FLYING WEATHER CONDITIONS OVER THE NEXT
24 HOURS ON LIGHT NORTHERLY SURFACE WINDS. THERE COULD BE SOME
SPOTTY GROUND FOG AROUND TOWARD DAYBREAK. HOWEVER...WITH DRIER
BOUNDARY LAYER AIR WORKING INTO THE REGION FROM THE NORTH...NOT
ANTICIPATING A REAL GOOD SET-UP FOR FOG TONIGHT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
DORN/NIPPER