Flash Flood Warning 6, NWS El Paso, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EL PASO TX/SANTA TERESA NM
233 PM MDT FRI JUL 19 2002

SYNOPSIS...
A PERSISTENT WEAK UPPER LEVEL DISTURBANCE REMAINS ANCHORED OVER THE
BORDER LAND. AT THE LOW LEVELS SOUTHEAST TO SOUTHWEST FLOW IS
CONVERGING OVER THE REGION TO KEEP A VERY MOIST AIR MASS STREAMING
INTO THE AREA FROM THE GULF OF MEXICO AND THE BAJA. THE DISTURBANCE
ALOFT AND DAYTIME HEATING IS CREATING DAYTIME INSTABILITY WHICH WILL
KICK OF DAILY ROUNDS OF SHOWERS AND THUNDERSTORMS THROUGH THE
WEEKEND. MANY OF THESE SHOWS WILL LINGER THROUGH THE NIGHT. BECAUSE
OF WEAK WINDS ALOFT STORMS WILL MOVE VERY SLOWLY...THUS LOCALLY
HEAVY RAIN AND ISOLATED AREAS OF ARROYO AND STREET FLOODING REMAINS
LIKELY ACROSS THE AREA. ALTHOUGH TEMPERATURES WILL REMAIN SLIGHTLY
BELOW NORMAL DUE TO CLOUD COVER...AFTERNOON CONDITIONS WILL BE
OPPRESSIVE DUE TO THE HIGH HUMIDITY.

DISCUSSION...
LARGER SCALE PATTERN SHOWS BROAD UPPER LEVEL HIGH CENTERED OVER
EASTERN COLORADO. A WEAK UPPER LEVEL DISTURBANCE IS ANCHORED OVER
THE CWFA ON THE BOTTOM SIDE OF THE HIGH PRESSURE DOME.  AT LOWER
LEVELS...H7 AND H85...A WEAK LOW IS EVIDENT IN THE WINDS FIELDS WITH
CYCLONIC FLOW CENTERED OVER THE CWFA. ITS TAKING A WHILE TO BREAK
OUT OF THIS MORNINGS CLOUD COVER ASSOCIATED WITH SHOWER ACTIVITY.
SEEING SOME TOWERS POP ALREADY WHERE THERE IS SOME DIFFERENTIAL SFC
HEATING WHERE THE CLOUDS HAVE BROKE. THIS SPEAKS TO THE AMOUNT OF
MOISTURE (1.54 PW IN EPZ 12Z SOUNDING) AND LEVEL OF INSTABILITY
OVER THE AREA.  WITH THE ENTIRE CWFA UNDER ABUNDANT DEEP MOISTURE
AND BROAD AREAS OF UPPER LEVEL INSTABILITY...ITS HARD TO MAKE
DISTINCTIONS ON WHERE AND WHEN THE TSTM AND SHOWERS WILL HIT.  HAVE
TO BROAD BRUSH THE POPS.  HOWEVER...THE CENTRAL CWFA SHOWS THE BEST
POTENTIAL WITH WEAK LOW LEVEL CONVERGENCE.  THE EAST HAS GOOD
POTENTIAL WITH THE DEEPEST MOISTURE.  WILL HAVE SCAT CAT POPS FOR ALL
AREAS TONIGHT.

AT H7 LEVELS...THE MODELS KEEP THE LOW OVERHEAD THROUGH THE WEEKEND
AND AVN EVOLVES IT INTO AN INVERTED TROUGH WHICH KEEP THE MOISTURE
PLUME FOCUSED OVER THE CENTER OF THE CWFA. MODELS ARE TRYING TO SHOW
SOME DRYING OUT WEST AS THE UPPER HIGH REFORMS OVER ARIZONA IN AN
ELONGATED SW-NE PATTERN...THAT MAKES FOR MORE NORTHERLY FLOW ALOFT
AND A THINNING OF THE SOUTHERLY MOIST FLOW. THIS WOULD MAKE POPS OUT
WEST MORE ISOLATED...BUT CERTAINLY NOT ELIMINATE THEM. THE EASTERN
AND CENTRAL CWFA LOOKS TO KEEP DEEPER MSTR THROUGH THE WEEKEND.

BY MONDAY...AVN SHOWS THE H7 TROF TO PUSH WEST INTO ARIZONA AS THE
RIDGE MOVES NORTH INTO THE ROCKIES.  THIS COMES WITH SOME DRYING FOR
THE EAST AND CENTRAL CWFA.  WELL KEEP POPS IN BUT LOWER THEM A BIT.
OF COURSE WITH WEAK SUMMER TIME PATTERNS AND THE SUBTLIES INVOLVED
IN THESE MICRO-SCALE FEATURES...SPLITTING HAIRS IS FRUITLESS.

EL PASO               BB  68/ 90/ 69/ 92/ 70  42423
LAS CRUCES            BB  65/ 89/ 66/ 91/ 67  42423
ALAMOGORDO            BB  65/ 88/ 66/ 89/ 67  42423
CLOUDCROFT            BB  46/ 68/ 45/ 70/ 45  35352
TRUTH OR CONSEQUENCES BB  66/ 90/ 64/ 92/ 65  43323
SILVER CITY           BB  57/ 83/ 58/ 85/ 59  34233
DEMING                BB  64/ 90/ 64/ 93/ 65  42323
LORDSBURG             BB  64/ 91/ 64/ 93/ 65  42323
SIERRA BLANCA         BB  65/ 89/ 66/ 91/ 67  42323

.ELP...NONE

14 / BIRD

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