AREA FORECAST DISCUSSION

 
 FXUS64 KEPZ 202053
 AFDEPZ
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE EL PASO TX/SANTA TERESA NM
 253 PM MDT SAT MAR 20 2010
 
 .SYNOPSIS...
 NORTHERLY WINDS BEHIND A COLD FRONT THAT PUSHED THROUGH THE REGION
 SATURDAY MORNING KEPT SATURDAY`S TEMPERATURES MUCH BELOW NORMAL.
 THIS NEW AIRMASS FILTERING IN ACROSS THE REGION WILL ALLOW FOR A
 COLD NIGHT TONIGHT. THE UPPER-LEVEL STORM SYSTEM THAT BROUGHT
 LIGHT LOWLAND RAIN AND MOUNTAIN SNOWS HAS EXITED THE REGION.
 CLEAR SKIES...LIGHT WINDS...AND DRY AIR WILL ALLOW FOR FREEZING
 TEMPERATURES TOMORROW MORNING FOR MOST LOCATIONS. HIGH PRESSURE
 ALOFT WILL BUILD INTO THE SOUTHWEST DESERTS SUNDAY. THE RESULTING
 WESTERLY WINDS WILL BRING DRIER AND WARMER WEATHER THROUGH
 TUESDAY. ANOTHER LOW PRESSURE SYSTEM WITH A COLD FRONT WILL MOVE
 INTO THE REGION WEDNESDAY BRINGING SLIGHT CHANCES FOR LOWLAND RAIN
 AND BETTER CHANCES FOR MOUNTAIN SNOW SHOWERS ALONG WITH COOLER
 TEMPERATURES. THE SYSTEM WILL RAPIDLY EXIT WITH CONDITIONS
 BECOMING DRY AND MILD THURSDAY THROUGH NEXT WEEKEND.
 
 &&
 
 .DISCUSSION...
 THIS AFTERNOON THE REGION SITS UNDER THE BACKSIDE OF THE EXITING
 UPPER-LEVEL STORM SYSTEM THAT BROUGHT WIND...RAIN/SNOW SHOWERS...
 AND COOLER TEMPERATURES TO THE BORDERLAND. ALOFT DEEP NORTHERLY
 FLOW IS IMPORTING DRIER AIR AS EVIDENCED BY CLOUD EROSION IN
 SATELLITE IMAGERY. AT THE SURFACE A NORTHERLY FLOW IS KEEPING
 COOLER AIR ADVECTING INTO THE REGION BEHIND AN OVERNIGHT COLD
 FRONTAL PASSAGE. TEMPERATURES ARE RUNNING WELL BELOW NORMAL THIS
 AFTERNOON...AND THAT HIGHLIGHTS OUR PRIMARY CONCERN FOR THE
 SHORT TERM.
 
 TONIGHT TEMPERATURES REGION-WIDE ARE EXPECTED TO DROP BELOW THE
 FREEZING MARK BY SUNRISE. THE FREEZE IS NOT EXPECTED TO BE DEEP OR
 EXTENDED...BUT SENSITIVE SPRING BLOOMS AND PETS MAY BE ADVERSELY
 AFFECTED. WILL ISSUE A SPECIAL WEATHER STATEMENT TO GET THE WORD
 OUT TO THE PUBLIC. OTHERWISE CLEARING SKIES DUE TO DRYING AND LIGHTER
 WINDS OVERNIGHT AND SUNDAY THROUGH MONDAY AS AN UPPER RIDGE ALOFT
 BUILDS OVER THE SOUTHWEST U.S.
 
 THE UPPER RIDGE WILL FLATTEN MONDAY INTO MONDAY NIGHT AS TWO
 UPPER LOWS TRACK EAST IN THE NORTHERN AND SOUTHERN BRANCHES OF A
 SPLIT-FLOW PATTERN ALOFT. THE SOUTHERN-BRANCH LOW IS COMPACT AND
 TRACKS EAST TOWARD THE CWFA ACROSS THE NORTHERN BAJA WHILE THE
 LARGER NORTHERN-BRANCH LOW TRACKS SOUTH TO THE FOUR CORNERS.
 CURRENT GFS SHOWS THE TWO SYSTEMS PHASING AS THEY APPROACH THE
 REGION. THIS GIVES THE AREA A RAPID-FIRE DOUBLE SHOT AS THE TWO
 SYSTEMS FOLLOW EACH OTHER OVER THE FORECAST AREA WEDNESDAY
 MORNING THROUGH THURSDAY MORNING. EFFECTS DON`T APPEAR TOO
 EXTREME. WINDS SHOULD BECOME BREEZY OR LOW-END WINDY TUE-THU WITH
 LEE TROUGHING DEVELOPING. MOISTURE IS LIMITED SO PRECIPITATION
 WILL GENERALLY BE LIGHT AND MOSTLY FOCUSED OVER THE MOUNTAINS. A
 BACKDOOR COLD FRONT IS PROGED TO PUSH IN WEDNESDAY NIGHT UNDER THE
 SECOND LOW...BUT COOLING LOOKS ONLY MODERATE AND LIMITED TO ONE
 DAY AT BEST. SO IT LOOKS LIKE WE`LL SEE A 24 HR PERIOD OF
 INCREASED CLOUDS...SLIGHT CHANCES FOR RAIN/SNOW...A PERIOD OF
 MODERATE TO WINDY CONDITIONS...AND SLIGHTLY BELOW NORMAL
 TEMPERATURES BUT NOTHING THAT LOOKS WORTHY OF STATEMENTS/WATCHES/
 ADVISORIES. 
 
 BEHIND THE EXIT OF THE MIDWEEK STORMS WE SHOULD SEE A GENERALLY
 ZONAL TO WEAKLY RIDGED PATTERN ALOFT. THIS WILL BRING WINDS BACK
 TO WEST AND KEEP WINDS LIGHT TO MODERATE. RESULTS WILL BE
 TEMPERATURES BACK TO NORMAL OR ABOVE. THIS WILL ALSO MARK A DRY
 PERIOD AS THE STORM TRACK IS SHOVED NORTH THROUGH THE WEEKEND.
 
 &&
 
 .AVIATION...VALID 21/00Z-22/00Z...  
 WINDS WILL DIMINISH AFTER SUNSET...WITH LIGHT/VARIABLE FLOW 
 CONTINUING INTO SUNDAY AFTERNOON.  VFR CONDITIONS WILL PREVAIL WITH 
 JUST FEW-SCT HIGH-BASED CU FOR THE REMAINDER OF THIS AFTERNOON.
 
 &&
 
 .FIRE WEATHER...
 COLD AIRMASS BEHIND YESTERDAY`S COLD FRONT WILL REMAIN IN PLACE 
 TONIGHT.  DIMINISHING WINDS WILL RESULT IN STRONG RAD COOLING WITH 
 FREEZING TEMPS EXPECTED IN ALL ZONES BY TOMORROW MORNING.  DESPITE 
 STRONG OVERNIGHT RECOVERY...FAIRLY DRY AIRMASS IN PLACE WILL KEEP 
 MIN RH VALUES IN THE LOWER TEENS ACROSS THE DESERT LOWLANDS OVER THE 
 NEXT FEW DAYS...HOWEVER LIGHT WINDS WILL PREVAIL.  TEMPERATURES WILL 
 QUICKLY RECOVER BACK TO NEAR SEASONAL NORMALS BY MONDAY AFTERNOON... 
 MEANING LOW/MID 70S FOR THE LOWLANDS.  
 
 UPPER LEVEL RIDGE AND A DEVELOPING INVERSION AROUND 700 MB WILL 
 RESULT IN LIMITED MIXING HEIGHTS AND LOW VENT RATES SUNDAY AND 
 MONDAY.  AN APPROACHING TROUGH WILL BRING INCREASING SOUTHWEST FLOW 
 BACK TO THE AREA TUESDAY...IMPROVING VENTILATION RATES.
 
 &&
 
 25-HARDIMAN
 
 
 .PRELIMINARY POINT TEMPS/POPS...
 EL PASO                 30  63  35  74  45 /   0   0   0   0   0 
 SIERRA BLANCA TX        26  61  33  73  44 /   0   0   0   0   0 
 LAS CRUCES              28  62  31  73  42 /   0   0   0   0   0 
 ALAMOGORDO              26  60  30  72  41 /   0   0   0   0   0 
 CLOUDCROFT              14  40  18  51  24 /   0   0   0   0   0 
 TRUTH OR CONSEQUENCES   25  61  31  70  40 /   0   0   0   0   0 
 SILVER CITY             21  56  26  65  34 /   0   0   0   0   0 
 DEMING                  26  62  30  72  41 /   0   0   0   0   0 
 LORDSBURG               27  62  32  73  41 /   0   0   0   0   0 
 
 &&
 
 .EPZ WATCHES/WARNINGS/ADVISORIES...
 NM...NONE.
 TX...NONE.
 &&
 
 

 
 14-BIRD
 
 
 

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