FXUS63 KOAX 020904
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
404 AM CDT TUE AUG 2 2011
.DISCUSSION...
FORECAST CHALLENGES INCLUDE AREAL COVERAGE OF HIGH HEAT INDICES
TODAY WITH A COLD FRONT WORKING THROUGH THE CWA...ALONG WITH
THUNDERSTORM CHANCES...ESPECIALLY LATE WEDNESDAY NIGHT AND
THURSDAY.
ONE MORE DAY OF HIGH HEAT TODAY...AS THIS BROAD HOT UPPER LEVEL
RIDGE IN PLACE ACROSS THE REGION GETS SHUNTED TO THE SOUTH AND
EAST. A COLD FRONT...JUST STARTING TO ENTER THE VERY FAR
NORTHWEST CORNER OF THE CWA...IS SET TO WORK THROUGH THE CWA
TODAY...AND AS IT DOES SO...IT WILL BRING COOLER AND DRIER AIR
INTO THE REGION. THE FRONT IS FORECAST TO BE MID-WAY THROUGH THE
CWA AT MID-DAY...SO CONCENTRATING A HEAT-RELATED HEADLINE TO
BASICALLY SOUTH OF THAT BOUNDARY LOCATION FOR THE EARLY AFTERNOON
THROUGH EARLY EVENING TIMEFRAME...WITH THE PREVIOUS HEAT ADVISORY
IN PLACE BEING UPGRADED TO AN EXCESSIVE HEAT WARNING.
TEMPWISE...ATTENTION FOR THE REMAINDER OF THE WEAK TURNS TO
CONDITIONS BECOMING CLOSER TO CLIMO NORMAL /MID TO UPPER 80S/ AS
THE VAST MAJORITY OF THE TIME...SOME FORM OF COOL EASTERLY
COMPONENT WIND IS OVER THE CWA /925HPA TEMPS GENERALLY IN THE LOW
TO MID 20S CELSIUS/.
THERE ARE A COUPLE OF NOTEWORTHY FORECAST PERIODS TO TALK ABOUT
REGARDING PRECIPITATION CHANCES. THE AFOREMENTIONED COLD FROPA
TODAY APPEARS TO BE ACCOMPANIED BY GREATER INSTABILITY BEHIND THE
BOUNDARY THAN IN FRONT OF THE BOUNDARY. PERHAPS BY PEAK
HEATING AS THE 700HPA MID-LEVEL THERMAL INVERSION BREAKS...THERE
COULD BE A FEW POST FRONTAL SHOWERS OR STORMS. HOWEVER...0-6KM
SHEAR IS PROGGED AT LESS THAN 20 KNOTS...SO SEVERE THUNDERSTORMS
APPEAR RATHER UNLIKELY TODAY. AS THIS UPPER RIDGE GETS KNOCKED
DOWN...THE UPPER FLOW PATTERN BECOMES A LITTLE BIT MORE WESTERLY
AND A BIT FASTER...WITH A GOOD-LOOKING SHORTWAVE PROGGED IN
SEVERAL MODELS TO WORK EAST ACROSS NEBRASKA WEDNESDAY THROUGH
THURSDAY...WITH PRECIPITATION CHANCES TAKING HOLD OF THIS CWA LATE
WEDNESDAY NIGHT AND PRETTY MUCH ALL DAY THURSDAY. THE OTHER
TIMEFRAME OF INTEREST IS FRIDAY NIGHT...SHOULD THERE BE A
SHORTWAVE IN THE FAST...HARD-TO-TIME...UPPER LEVEL WESTERLIES.
MODELS PROG A QUASI-STATIONARY BOUNDARY TO BE IN PLACE ACROSS THE
REGION JUST SOUTH OF THIS CWA...WITH THE NOSE OF A 25 TO 35 KNOT
LLJ PROGGED TO BE POINTING INTO THE SOUTHERN HALF OF THE CWA.
DORN
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
COLD FRONT WILL MOVE ACROSS THE AREA TODAY FROM NORTHWEST TO
SOUTHEAST. THE FRONT WILL BRING AN ABRUPT CHANGE FROM SOUTHEAST TO
NORTHWEST WINDS...WITH AND INCREASE TO 10 TO 20 KTS. COULD SEE SOME
THUNDERSTORMS FIRE ALONG AND BEHIND THE FRONT...HOWEVER BETTER
DYNAMICS DEVELOP LATER IN THE DAY...AFTER THE FRONT HAS PUSHED SOUTH
OF THE TAF SITES. WILL KEEP FORECAST DRY FOR NOW AS LOW CONFIDENCE
IN DEVELOP BUT WILL MONITOR CLOSELY.
MASEK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR NEZ045-
051>053-065>068-078-088>093.
IA...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR IAZ055-
056-069-079-080-090-091.
&&
$$
99