Severe Thunderstorm Warning 4, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
136 PM CDT FRI APR 6 2001

...FORECAST CHALLENGE WILL BE POPS AND WINDS TONIGHT...

CURRENT WATER VAPOR IMAGERY SHOWING SHORTWAVE EDGING EAST WITH
SOUTHWEST WINDS OVER NORTHEAST COLORADO TO AID IN PUSHING WARM
FRONT TO THE NORTHEAST. AREAS OF FOG AND LOW CEILING ON THE RISE
WITH A RAPID WARMUP EXPECTED DURING THE AFTERNOON. 17Z HAND SURFACE
ANALYSIS HAD 994 MB LOW WEST OF DEN WITH SEMI STATIONARY FRONT
DRAPED FROM CENTRAL MONTANA THROUGH EASTERN WYOMING CUTTING THROUGH
NORTHEAST COLORADO THEN EAST THROUGH NORTHERN KANSAS INTO NORTHERN
MISSOURI.

MODELS ARE SLOWER IN THE PROGRESSION FOR TODAY BUT CONSISTENT WITH
SYSTEM TO LIFT NORTHEAST OVERNIGHT. PLACEMENTS WITH THE UPPER
FEATURES ARE IN QUESTION WITH A BLEND OF ETA/AVN USED.

THIS EVENING THUNDERSTORMS SHOULD RAPIDLY FIRE AND MOVE NORTHEAST
INTO SOUTHWEST NEBRASKA. FEW LIGHTNING STRIKES EVIDENT ALREADY IN
KANSAS WHERE SOME CLEARING HAS OCCURRED. THE SLOW EROSION OF THE
STRATUS FIELD SHOULD NOT LESSON THREAT FOR THIS EVENING FROM 5 PM
UNTIL MIDNIGHT WHEN MAIN FORCING OF SYSTEM IS PROGGED TO LIFT
NORTHEAST. THE WARM FRONT MOVES INTO THE SOUTHWEST NEAR 5 PM AS
SERIES OF SHORTWAVES EMBEDDED IN THE FLOW MOVE ACROSS. INCREASING
DIVERGENCE ALOFT ASSOCIATED WITH H3 JET WILL PROVIDE INCREASED LIFT
WITH GOOD WARM AIR ADVECTION AHEAD OF SYSTEM. BY 03Z SURFACE LOW
MAY BE EAST OF IML WITH GOOD 500-300 MB QVECTOR CONVERGENCE FOCUS
JUST NORTH OF INTERSTATE 80 FROM LISCO TO STAPLETON...THEN LOW RACES
TO THE NORTH CENTRAL BY 06Z. SURFACE LOW BEGINS TO OCCLUDE BY 06Z AS
5H LOW CLOSES OFF WITH SYSTEM TO BECOME STACKED WHILE MOVING THROUGH
EASTERN SOUTH DAKOTA. A SECONDARY COLD FRONT WILL SWING SOUTHEAST
FROM 06Z-09Z WITH SHOWERS ROTATING BACK INTO THE NORTHWEST AND
NORTH CENTRAL THROUGH MID MORNING. WHILE SUBSIDENCE INCREASES ACROSS
THE SOUTHWEST AND CLEARING BY DAYBREAK. WINDS DO POSE A PROBLEM WITH
THE GRADIENT MORE RELAXED THAN LAST TWO RUNS. BUT WINDS WILL REACH
ADVISORY CRITERIA BY OR SHORTLY AFTER MIDNIGHT AND WILL HIGHLIGHT
WITH WINDS DIMINISHING IN THE MORNING WEST AND NORTH CENTRAL BY
AFTERNOON. TEMPERATURES TONIGHT WILL BE SLOW TO DROP OFF WITH CLOUDS
LINGERING. COOLEST READINGS TO BE OVER THE PANHANDLE ND CLOSE TO
GUIDANCE.

SATURDAY WINDS DIMINISH AS THE LOW LIFTS NORTHEAST TOWARD THE
NORTHERN LAKES. SOME HIGH CLOUDINESS WILL MOVE INTO THE NORTHWEST
OTHERWISE DRY AND WARMER. GUIDANCE CLOSE AND FOLLOWED. FRIDAY NIGHT
A WARM FRONT WILL MOVE EAST NORTHEAST AS THE AREA OF LOW PRESSURE
FORMS TO THE SOUTHWEST..WITH THE FRONT EXTENDING EAST ACROSS
CENTRAL NEBRASKA BY 08/06Z. FEW SHOWERS MAY OCCUR OVER THE NORTH AND
ELEVATED IN NATURE. THEN SUNDAY THE SEMI-STATIONARY FRONT MOVING BACK
TO THE SOUTH AS THE SURFACE HIGH BUILDS INTO THE NORTHERN PLAINS.
WEAK DISTURBANCES MOVE ACROSS WITH MAINLY MID AND HIGH LEVEL
CLOUDINESS.

SUNDAY NIGHT THE FRONT REMAINS NEARLY STATIONARY WITH EAST WINDS
ACROSS THE AREA TO INCREASE BOUNDARY LAYER MOISTURE WEST...WITH
AREAS OF FOG AND PATCHY DRIZZLE.

IN THE EXTENDED NO CHANGES MADE WITH FRIDAY PERIOD ADDED WHEN WARM
FRONT MOJVES EAST WITH DRY CONDITIONS IN NORTHWEST FLOWS.

.LBF...WIND ADVISORY WESTERN AND NORTH CENTRAL FROM MIDNIGHT TO
NOON SATURDAY...

TLK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE, NE
341 PM CDT FRI APR 6 2001

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0330 PM    5 SE ERICSON              NE   1.00 INCH HAIL
04/06/01   WHEELER

0338 PM    4 NE ERICSON              NE   1.00 INCH HAIL
04/06/01   WHEELER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE, NE
413 PM CDT FRI APR 6 2001

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0345 PM    4 S BARTLETT              NE   1.75 INCH HAIL
04/06/01   WHEELER                        GOLFBALL HAIL COVERED THE
                                          GROUND

DP