FXUS63 KOAX 270802
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
302 AM CDT WED JUL 27 2011
.DISCUSSION...
MAIN FORECAST CONCERNS ARE CONVECTION OVER THE NEXT SEVERAL DAYS
AS WE HEAD BACK INTO A MORE ACTIVE WEATHER PATTERN. SECONDARY
CONCERN WOULD BE TEMPERATURES TODAY WITH ONE MORE HOT DAY AND HIGH
HEAT INDEX VALUES EXPECTED.
MCS MOVING THROUGH CENTRAL AND NOW INTO EASTERN NEBRASKA IS THE
IMMEDIATE CONCERN...AND WILL BE ONGOING AT FORECAST ISSUANCE...
ALTHOUGH IT IS MOVING NORTHEAST...AND THE SOUTHERN EDGE IS
GENERALLY EXPECTED TO REMAIN NORTH OF I80 AFTER 12Z...AFFECTING
PRIMARILY NORTHEAST NEBRASKA AND NORTHWEST IOWA. IN ITS WAKE...
SOUTHERLY WINDS AHEAD OF A SURFACE TROUGH...ALONG WITH CLEARING
SKIES SHOULD ALLOW TEMPERATURES TO WARM CONSIDERABLY... BUT THE
CONCERN IS WHETHER THEY WOULD WARM ENOUGH TO REACH HEAT ADVISORY
CRITERIA BEFORE CONVECTION REDEVELOPS LATER THIS AFTERNOON AS THE
SURFACE TROUGH SETTLES IN. BELIEVE IT CAN... AND WILL LET THE
ADVISORY REMAIN IN EFFECT...AND WILL LET THE DAY SHIFT MAKE LATE
MORNING ADJUSTMENTS IF NECESSARY. REGARDING SEVERE WEATHER THREAT
LATER THIS AFTERNOON AND EVENING...INCREASING INSTABILITY ALONG
WITH 40 TO 50KTS OF BULK SHEAR SHOULD BE SUFFICIENT FOR A SEVERE
STORM THREAT FOR WIND AND HAIL. UNSURE ABOUT TORNADO THREAT...BUT
PERHAPS IF A DISCRETE CELL OR TWO COULD DEVELOP BEFORE A LINEAR
MCS DEVELOPS...IT COULDNT BE RULED OUT. WILL FOCUS HIGHEST POPS
OVERNIGHT ALONG THE I80 CORRIDOR WHERE THE SLOW MOVING COLD FRONT
SETS UP.
FOR THURSDAY...THE FRONT ESSENTIALLY STALLS ACROSS NORTHEAST
KANSAS AND NORTHERN MISSOURI AND WILL CONTINUE TO BE A FOCUS FOR
THUNDERSTORM DEVELOPMENT THROUGH THE DAY THURSDAY...AND ESPECIALLY
THURSDAY NIGHT. THROUGH THIS PERIOD...HAVE HIGHEST CHANCE OF RAIN
ALONG AND SOUTH OF INTERSTATE 80...AND STILL A LINGERING CHANCE OF
THUNDERSTORMS SOUTHEASTERN HALF OF THE CWFA ON FRIDAY.
THEREAFTER...CHANCE FOR PRECIP BECOMES SIGNIFICANTLY LOWER AS A
RIDGE REESTABLISHES ITSELF ACROSS THE PLAINS...AND TEMPERATURES
BECOME HOT AND OPPRESSIVE ONCE AGAIN...MOVING BACK INTO THE 90S
FOR DAYTIME HIGHS. MADE NO SIGNIFICANT FORECAST CHANGES BEYOND
SUNDAY.
DEWALD
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
SCATTERED THUNDERSTORMS THAT MOVED INTO NERN NEBRASKA AFTER 27/06Z
TAF ISSUANCE WERE EXPECTED TO STAY NW OF KLNK/KOMA THIS MORNING BUT
TRENDS CLOSELY MONITORED AS SWD DEVELOPMENT CONTINUED AS OF 27/07Z.
OTHERWISE THIS COMPLEX SHOULD DEPART ERN NEBRASKA FAIRLY EARLY THIS
MORNING LEAVING VFR CONDITIONS IN ITS WAKE. THE STORMS WILL HELP
PUSH A WEAK COLD FRONT INTO ERN NEBRASKA THIS AFTERNOON AND
REDEVELOPMENT OF THUNDERSTORMS PROBABLE...TIMING OF WHICH WAS
UNCERTAIN WITH 27/06Z ISSUANCE SO NO ADDITIONAL TSTM MENTION WAS
MADE THEN. HOWEVER...LATER TAFS MAY INCLUDE TSTMS AS THREAT BECOMES
BETTER DEFINED.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ052-053-066>068-
088>093.
IA...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ069-079-080-090-
091.
&&
$$