Severe Thunderstorm Warning 135, NWS North Platte, NE

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
219 PM CDT TUE JUL 3 2001

...CONVECTIVE POPS WILL BE A CHALLENGE EACH NIGHT...

UPPER PATTERN FEATURES A LARGE RIDGE OVER WESTERN NOAM AND
SIGNIFICANT TROFING IN EASTERN NOAM. AT THE SURFACE...A STATIONARY
FRONT EXTENDS FROM CENTRAL IA...TO SOUTHERN NEBRASKA...INTO LOW
PRESSURE IN NORTHEASTERN CO.

CONVECTIVE DEBRIS FROM MCS OVER ERN WY/WRN SD LAST NIGHT CONTINUES
TO WEAKEN OVER NORTHERN ZONES. CLOUDINESS HAS EFFECTIVELY REMOVED
THOSE AREAS FROM THREAT OF CONVECTION THIS EVENING AS TEMPS ARE
STRUGGLING TO SURPASS 70. FARTHER SOUTH AND WEST...CONDITIONS ARE
MORE FAVORABLE WHERE AXIS OF HIGHEST CAPES AND MOISTURE CONVERGENCE
CURRENTLY EXIST. MODELS RESOLVED THIS WELL AND MAINTAIN THIS
ENVIRONMENT INTO THE EVENING. NO SIGNIFICANT WAVES EXPECTED THROUGH
THE AREA BUT THE HI-RES ETA DID RESOLVE A FEW SMALL CONVECTIVE
CLUSTERS INTO THE FAR WEST TONIGHT. ERN WY/WRN NE WILL REMAIN IN
LEFT EXIT REGION OF UPPER LEVEL SPEED MAX SO THERE MAY BE ENHANCED
DIVERGENCE ALOFT TO SUPPORT CONVECTION.

NOT SURE WHY THE AVN HAS RESOLVED COOL MAXES WED...IN SOME CASES THE
NGM HAS DONE LIKEWISE. NEARLY FULL SUNSHINE IS EXPECTED...GIVEN TRACK
RECORD OF MODELS AND ESPECIALLY GUIDANCE IN THE PAST WEEK WILL GO
WITH ETA SURFACE TEMPS WHICH WILL BE MUCH ABOVE MOS MAXES. LOW LEVEL
TEMP PROFILES LOOK VERY SIMILAR TO THOSE DURING THE PAST WEEK WHEN
90S WERE COMMON ACROSS THE CWA. INSTABILITY WILL INCREASE STEADILY
AGAIN WITH MOISTURE CONVERGENCE FAVORING THE WEST AND NORTHWEST.

RIDGE RUNNER EXPECTED TO DROP THROUGH ERN WY/NE PANHANDLE FROM 00Z
TO 06Z THU WHILE AT SAME TIME MODELS DEVELOP A 30 TO 35 KNOT LOW
LEVEL JET INTO THE CWA. PLENTY OF INSTABILITY...MOISTURE AND
CONVERGENCE RESOLVED IN THE MODELS...SO MCS POTENTIAL LOOKS GOOD OVER
THE WEST.

SEVERAL FACTORS SUGGEST THURSDAY WILL BE DRY. LARGE SCALE SUBSIDENCE
INDICATED IN LAYER Q-VECS...MID LEVEL LAPSE RATES ARE RESOLVED TO
BE STABLE INDICATING ENVIRONMENT WILL HAVE BEEN WORKED OVER IN WAKE
OF MCS...AND COOL SURFACE HIGH MOVING SOUTHWARD THROUGH MN/IA WILL
INCREASE CAA INTO THE CWA. THUS THINK ETA SURFACE BASED INSTABILITY
MAY BE OVERDONE AND NOT SO CONCERNING GIVEN OTHER FACTORS. 24 HR
CHANGE OF TEMPS AT H85 OF 3 TO 5 C SUPPORTS COOLER GUIDANCE MAXES.

IN THE EXTENDED...MEDIUM RANGE GUIDANCE RESOLVES NO CHANGE FRIDAY.
NEXT RIDGE RUNNER SATURDAY WITH CHANCE OF CONVECTION. DRY AGAIN
SUNDAY THROUGH TUESDAY AS RIDGING REMAINS IN PLACE WITH AN ABSENCE
OF WAVES.

.LBF...NONE.

DJB