Hail and Damaging Wind in Nebraska, May 10, 2001

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
205 PM CDT THU MAY 10 2001

...FORECAST CHALLENGE TO BE CONVECTION CHANCES TONIGHT...

H2 JET NOSING IN TO WESTERN SD EVIDENT ON WATER VAPOR IMAGERY...HAS
ENHANCED CONVECTION SOME OVER BLACK HILLS AREA.  SURFACE FRONT
CONTINUES TO SLIDE SOUTH OF CWA...TAKING MAIN RISK OF SEVERE
WEATHER WITH IT. ETA APPEARS TO HAVE A GOOD HANDLE ON SURFACE FRONTAL
POSITION.

TONIGHT...WITH NORTH AND NORTHEAST SURFACE WINDS ACROSS CWA...
WHILE SHOWERS ARE POSSIBLE IN WEST AND NORTH AREAS...THINK THERE WILL
BE LITTLE OR NO RISK OF SEVERE WX IN OUR CWA. VORT MAX ENTERING
NORTHERN PART OF CWA TONIGHT MAY PRODUCE SOME THUNDERSTORMS
OVER NORTH CENTRAL ZONES (AND BLACK HILLS). SOME MOISTURE WILL BE
ROBBED BY CONVECTION SLATED TO DEVELOP ALONG THE FRONT TO THE SOUTH.
THETA-E RIDGE EXTENDING FROM FRONT NORTHWARD THROUGH PANHANDLE WILL
ENCOURAGE SOME -TSRA OR SHRA ACTIVITY. 12Z SOUNDING SHOWS THAT ETA IS
ONCE AGAIN OVERESTIMATING DEWPOINTS...BUT OTHERWISE SEEMS TO HAVE
FEATURES IN THE RIGHT LOCATION. THETA-E RIDGE OVER PANHANDLE RECEDES
TOWARD 12Z SO DO NOT EXPECT ANY SHOWER ACTIVITY IN THE WEST TO MAKE
IT VERY FAR EAST BEFORE FIZZLING OUT. AVN DEVELOPS PRECIP MORE ALONG
AND NORTH OF FRONT.  WITH CURRENT DEWPOINTS IN THE MID 40S...WILL
FAVOR SOMEWHAT LOWER TEMPS OVERNIGHT...SIDING WITH AVN NUMBERS. AVN
PROGS MCS TO DEVELOP AROUND 06Z SOMEWHERE IN SOUTH CENTRAL NEB...
MOVING SOUTHEAST. MOST OF CWA SHOULD BE OUT OF PCPN BY 12Z FRI.
QUESTION IS THEN WILL THERE BE ANY STRATUS ADVECTING WESTWARD FROM
MCS BY DAWN INTO OUR AREA. ETA INDICATES THAT ANY STRATUS THAT DOES
FORM SHOULD DISSOLVE UNDER SUBSIDENCE BY 18Z.

FRIDAY...WITH SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTHEAST...
FRONT WILL GET FURTHER PUSHED SOUTH. WEAK COLD AIR ADVECTION TO
CONTINUE...BUT WILL BE OFFSET SOME IN MID ZONES BY INSOLATION. HIGH
TEMPS IN THE 70 TO 75 RANGE SHOULD BE GOOD FOR MOST LOCATIONS.
FRIDAY NIGHT...LOW LEVEL JET CRANKS UP ON THE WEST SIDE OF SURFACE
HIGH.  THINK WE WILL REMAIN DECOUPLED...BUT COULD ADVECT IN SOME
MOISTURE KEEPING LOW TEMPS UP A TAD.

SATURDAY...H7 OMEGA BULLSEYE OVER EASTERN SD MAY PRODUCE SOME
SHOWERS THAT SLIDE INTO NORTH CENTRAL ZONES DURING MORNING HOURS.
CURRENT PROGS LOOK LIKE BULK OF PCPN WILL MISS HOLT COUNTY. AVN
DOES NOT HAVE THIS FEATURE AT ALL.  WILL LEAVE FORECAST DRY FOR THAT
AREA FOR NOW. TEMPS SHOULD WARM A FEW DEGREES SATURDAY FROM FRIDAY
HIGHS.

EXTENDED...MRF STILL ADVERTISING UPPER LEVEL RIDGE TO POSITION
ITSELF OVER WESTERN NEB THIS WEEKEND. LEE SIDE TROUGH FORMING SUNDAY
WILL REALLY HELP WARM THINGS UP PROVIDED WE GET ADEQUATE MIXING. 90
NOT OUT OF THE QUESTION...AND MAY BE A BIT UNDERDONE IF THERE IS
WIND. MOISTURE LIMITED WELL ENOUGH DESPITE SHORTWAVE COMING THROUGH
MONDAY THAT DRY FORECAST SEEMS REASONABLE.  AFTER MONDAY WE
TRANSITION TO NORTHWEST FLOW...ON THE DOWN SIDE OF UPPER LEVEL RIDGE
IN THE WEST. DRY WEATHER WILL BE THE RULE.  MRF PATTERN IN LATER
PERIODS LOOKS A LITTLE CHAOTIC/UNRELIABLE.  THINK THE RIDGE
WILL CONTINUE TO BUILD AND TRY TO SHIFT EAST SOME...KEEPING THE WEEK
DRY...WARMING SOLME EACH DAY.

.LBF...NONE.

SLM