VALID 031200Z – 041200Z

…THERE IS A SLGT RISK OF SVR TSTMS ACROSS CENTRAL/SOUTHERN NM AND
SOUTHEAST AZ…

…SYNOPSIS…
TO THE SOUTH OF AN INCREASINGLY PROGRESSIVE BELT OF WESTERLIES OVER
CANADA…AN AMPLIFIED LARGE SCALE PATTERN WILL PERSIST OVER THE
CONUS THROUGH THE PERIOD. AN UPPER LOW WILL CONTINUE TO WEAKEN/SHIFT
WEST OF THE MS RIVER…FLANKED BY A BUILDING UPPER RIDGE OVER MUCH
OF THE EASTERN SEABOARD AND A SLIGHTLY WEAKENING WESTERN STATES
UPPER RIDGE.

…NM AND CENTRAL/SOUTHEAST AZ AND SOUTHERN CO…
INTO THIS AFTERNOON/EVENING…THE OVERALL PATTERN/SCENARIO OVER THE
REGION WILL HAVE CHANGED RELATIVELY LITTLE FROM TUESDAY…WITH A
RELATIVELY MOIST AIRMASS ACROSS THE REGION IN CONJUNCTION WITH
RELATIVELY STRONG NORTHERLY MID-HIGH LEVEL WINDS. AT LEAST WIDELY
SCATTERED IF NOT SCATTERED TSTMS ARE LIKELY TO DEVELOP/INCREASE
THROUGH THE AFTERNOON ACROSS PARTS OF CENTRAL/SOUTHERN CO AND
ESPECIALLY NM. SUFFICIENT SHEAR/DESTABILIZATION WILL EXIST FOR
SUSTAINED MULTICELLS/PERHAPS SOME BRIEF SUPERCELLS CAPABLE OF
ISOLATED INSTANCES OF SEVERE HAIL. BY LATE AFTERNOON…STORMS ARE
LIKELY TO CLUSTER/ORGANIZE INTO LINEAR BANDS WHILE PROPAGATING
SOUTH-SOUTHWESTWARD ACROSS THE SOUTHERN HALF OF NM AND PERHAPS ONTO
THE DESERT FLOOR OF SOUTHEAST AZ THROUGH EARLY/MID EVENING.

…SOUTHEAST STATES/APPALACHIANS…
WHILE UPPER HEIGHT RISES WILL CONTINUE TO OCCUR OVER THE REGION…A
RELATIVELY MOIST AIRMASS /NEAR OR ABOVE 70F SURFACE DEWPOINTS/ WILL
REMAIN ALONG/EAST OF A PERSISTENT NORTHEAST-SOUTHWEST ORIENTED
FRONTAL ZONE…BENEATH A MODERATE BELT /25-35 KT/ OF SOUTHERLY
MID-LEVEL WINDS. WIDELY SCATTERED SHOWERS/TSTMS WILL REMAIN QUITE
COMMON…WITH TSTMS MORE PREVALENT INTO THE AFTERNOON INCLUDING THE
POSSIBILITY OF SOME STRONGER/POSSIBLY SEVERE TSTMS CAPABLE OF
DOWNBURSTS. BUT…SIMILAR TO YESTERDAY…THE PROXIMITY OF THE UPPER
RIDGE/WEAK LAPSE RATES ALOFT AND RELATIVELY LIMITED DESTABILIZATION
SHOULD LIMIT THE OVERALL SCOPE/MAGNITUDE OF THE SEVERE RISK.

POTENTIAL FOR LOCALIZED WIND DAMAGE ASIDE…SOME TRANSIENT
SUPERCELLS AND POTENTIALLY ISOLATED/BRIEF TORNADO POTENTIAL WILL
EXIST THIS AFTERNOON INTO TONIGHT ACROSS PARTS OF THE SOUTHEAST
STATES…ESPECIALLY IF LOW-LEVEL FLOW INDEED STRENGTHENS THIS
AFTERNOON INTO TONIGHT IN CONJUNCTION WITH A LOW ALONG THE GULF
COAST/INTERIOR SOUTHEAST STATES AS PROGGED BY VARIOUS 00Z-BASED
NUMERICAL GUIDANCE. EVEN SO…ANY SUCH POTENTIAL WILL LIKELY BE
TEMPERED BY TONIGHT VIA A SLIGHTLY COOLER NOCTURNAL BOUNDARY LAYER.

…MIDWEST/GREAT LAKES…
AS HAS BEEN THE CASE OVER THE PAST FEW DAYS…WEAK DESTABILIZATION
WILL OCCUR THIS AFTERNOON TO THE EAST-NORTHEAST OF A WEAK SURFACE
LOW AND IN VICINITY OF A WEAK/PERSISTENT FRONT AND/OR SURFACE
TROUGH. MODERATELY STRONG SOUTH-SOUTHWESTERLY MID-LEVEL WINDS WILL
CONTRIBUTE TO SUFFICIENT VERTICAL SHEAR FOR SOME SEMI-SUSTAINED
MULTICELLS AND PERHAPS A FEW TRANSIENT SUPERCELLS /MOST PROBABLE
ACROSS NORTHERN PORTIONS OF INDIANA AND OH INTO LOWER MI/. LOCALIZED
BOUTS OF WIND DAMAGE/MARGINALLY SEVERE HAIL WILL BE POSSIBLE THIS
AFTERNOON/EARLY EVENING IN AREAS FROM NEAR THE MIDDLE OH RIVER
VALLEY NORTHWARD INTO LOWER MI.

…GREAT BASIN/NORTHERN INTERMOUNTAIN REGION…
ANOTHER DAY OF WIDELY SCATTERED TSTMS ARE ANTICIPATED WITHIN A
RELATIVELY MOIST AIRMASS ON THE PERIPHERY OF THE FLATTENING UPPER
RIDGE. SOME OF THE STRONGER STORMS WILL BE CAPABLE OF DOWNBURSTS AND
POSSIBLY MARGINAL HAIL FROM THE SIERRA NEVADA EASTWARD INTO PARTS OF
ID/NORTHERN UT AND WY.

…NORTHEAST MT/WESTERN ND…
NEAR A SOUTHEASTWARD-ADVANCING FRONT…STORMS MAY DEVELOP
ACROSS/INTO PORTIONS OF NORTHEAST MT/WESTERN ND LATE THIS AFTERNOON
AND ESPECIALLY TONIGHT. SHOULD THIS OCCUR…ISOLATED BOUTS OF SEVERE
WINDS AND/OR HAIL WILL BE POSSIBLE.

..GUYER/LEITMAN.. 07/03/2013