Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 240549
SWODY2
SPC AC 240548

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1248 AM CDT THU JUL 24 2014

VALID 251200Z - 261200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
ISOLATED SEVERE STORMS WILL BE POSSIBLE OVER PARTS OF THE UPPER
MIDWEST TO CENTRAL HIGH PLAINS.

...SYNOPSIS...
A VIGOROUS MID-LEVEL CYCLONE IN THE LEE OF THE CANADIAN SRN ROCKIES
SHOULD GRADUALLY SHIFT E TO THE SRN SK/MB BORDER AREA BY EARLY SAT.
THIS WILL EFFECTIVELY DAMPEN THE NRN PLAINS/UPPER MIDWEST
RIDGE...TRANSITIONING TO A ZONAL FLOW REGIME WITH A MID-LEVEL
ANTICYCLONE ANCHORED OVER NM. AT THE SURFACE...A THERMALLY-AIDED
CYCLONE SHOULD BE INDUCED OVER THE LOWER MO VALLEY WITH A WARM FRONT
EXTENDING SE TO THE MID-MS VALLEY. TRAILING QUASI-STATIONARY FRONT
WILL ARC W TO THE CNTRL HIGH PLAINS WHERE LEE CYCLOGENESIS WILL
OCCUR.

...CNTRL HIGH PLAINS...
GUIDANCE DIFFERS WITH THE DEGREE OF CYCLOGENESIS INVOF SE WY FRI
AFTERNOON. THE DEEPER NAM TENDS TO FAVOR GREATER LOW-LEVEL MOISTURE
AND CONSEQUENTLY LARGER POTENTIAL BUOYANCY THAN OTHER GUIDANCE. THE
LACK OF APPRECIABLE UPSTREAM MID-LEVEL IMPULSES AND FARTHER S
MID-LEVEL JET RELATIVE TO OTHER GUIDANCE...RENDERS LOW CONFIDENCE IN
THIS SCENARIO. AT A MINIMUM...ISOLATED HIGH-BASED CONVECTION SHOULD
FORM ACROSS PARTS OF THE FRONT RANGE FRI AFTERNOON WHERE DEEP
INVERTED-V THERMODYNAMIC PROFILES AMIDST A TIGHT MID-LEVEL FLOW
GRADIENT WOULD SUPPORT LOCALIZED SEVERE WIND GUSTS. FRI
EVENING/NIGHT...LOW-LEVEL E/SELYS WILL STRENGTHEN YIELDING UPSLOPE
AND WAA THAT SHOULD RESULT IN A BAND OF ELEVATED CONVECTION
OVERNIGHT ACROSS PARTS OF SRN SD/NRN NEB. ALTHOUGH THE DEGREE OF
BUOYANCY IS UNCERTAIN...VERY STRONG CLOUD-BEARING SHEAR AND STEEP
MID-LEVEL LAPSE RATES WOULD FAVOR SEVERE HAIL PRODUCTION.

...LOWER MO AND MID/UPPER MS VALLEYS...
ROBUST LOW-LEVEL WAA SHOULD YIELD ELEVATED TSTM CLUSTERS CENTERED
OVER THE UPPER MS VALLEY AT 12Z/FRI...ALONG THE FRINGE OF A STOUT
PLAINS EML. THIS CONVECTION SHOULD SUBSIDE DURING THE DAY AS THE LLJ
WEAKENS. IN THE WAKE OF THIS ACTIVITY...PRONOUNCED CAPPING SHOULD
EXIST OVER MUCH OF THE WARM SECTOR WITH 700 MB TEMPERATURES OF 12-16
DEG C. DESPITE POTENTIAL FOR A VERY UNSTABLE AIR MASS...CONFIDENCE
IN SUSTAINING SURFACE-BASED TSTMS IS RATHER LOW. THE BEST PROSPECT
WOULD BE NEAR THE THERMAL LOW WHERE HOT SURFACE TEMPERATURES WILL
YIELD WEAKER INHIBITION AND SUFFICIENT CONVERGENCE MAY EXIST TO
INITIATE A STORM OR TWO. IF THIS OCCURS WITHIN THE PERIPHERY OF
MODERATE MID-LEVEL W/NWLYS...LARGE HAIL AND SEVERE WIND GUSTS WOULD
BE POSSIBLE. FARTHER E ACROSS PARTS OF THE MID/UPPER MS
VALLEY...ELEVATED STORMS SHOULD REDEVELOP FRI EVENING/NIGHT AS THE
LLJ STRENGTHENS. ON THE WRN PERIPHERY OF THIS DEVELOPMENT...STEEP
MID-LEVEL LAPSE RATES WOULD SUPPORT A RISK FOR MARGINALLY SEVERE
HAIL.

...NRN MN...
COOLER 700 MB TEMPERATURES RELATIVE TO AREAS FARTHER S SHOULD RESULT
IN MINIMAL INHIBITION AT PEAK HEATING. A MODERATELY FAVORABLE
COMBINATION OF INSTABILITY/SHEAR WOULD SUPPORT A RISK FOR AT LEAST
MARGINALLY SEVERE HAIL/WIND. HOWEVER...LOW-LEVEL FLOW WILL BE ANEMIC
WITH CONVERGENCE ALONG A COLD FRONT EXPECTED TO BE WEAK. CONFIDENCE
IS LOW IN THE DEVELOPMENT OF MORE THAN A COUPLE OF SURFACE-BASED
STORMS.

..GRAMS.. 07/24/2014




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