Christine Hudnall

Edited:

Yeah! Back to normal now, forecast and discussion has been updated. :) We are no longer under a SEE TEXT, but a SLGT risk now.

…FL…
SIMILAR SETUP ACROSS FL PENINSULA TO WED WITH STEEPER THAN USUAL LAPSE RATES ALONG WITH DRIER AIR IN MID LEVELS. AFTERNOON THUNDERSTORMS WILL INITIATE VICINITY E COAST SEA BREEZE BOUNDARY IN THE N AND OUTFLOW BOUNDARIES IN THE S WHERE THERE IS ONGOING ELEVATED CONVECTION. PRIMARY THREAT WILL BE MARGINALLY SEVERE HAIL
AND WET MICRO BURSTS.

Here is the Forecast Discussion that went with it:

SPC AC 190601

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0101 AM CDT THU JUN 19 2008

VALID 191200Z - 201200Z

…THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL AND SRN PLAINS…

…SYNOPSIS…
A PERSISTENT AND SEASONABLY COLD UPR LOW OVER SERN CANADA WILL SHIFT SLOWLY NE TODAY…WHILE THE SUBTROPICAL RIDGE OVER MEXICO BUILDS N. IN BETWEEN THESE SYSTEMS…A MODESTLY FAST FLOW REGIME WILL EXIST… CARRYING NUMEROUS MID-LEVEL SHORTWAVE TROUGHS FROM THE E PAC BASIN/ WRN U.S. TO THE PLAINS.

…CENTRAL/SRN PLAINS…
WATER VAPOR IMAGERY INDICATED A SHORT WAVE TROUGH MOVING EWD AT THIS TIME ACROSS THE GREAT BASIN. THERE ARE EXPECTED TO BE ONGOING CLUSTERS OF TSTMS OVER MUCH OF NEB…WITH EXTENSIVE CLOUD DEBRIS LIKELY INHIBITING THE ONSET OF SURFACE HEATING ACROSS PARTS OF THE CENTRAL PLAINS THIS MORNING. THE TRAILING PORTION OF A SURFACE
TROUGH MOVING EWD THROUGH THE UPPER MS VALLEY TODAY SHOULD EXTEND WWD ALONG THE SD/NEB BORDER THIS AFTERNOON.

SURFACE HEATING WITHIN A MOIST AIR MASS /SURFACE DEWPOINTS IN THE 60S/ COMBINED WITH 7-7.5 C/KM MID LEVEL LAPSE RATES SHOULD RESULT IN MODERATE INSTABILITY ACROSS MUCH OF THE CENTRAL/SRN PLAINS BY PEAK HEATING.

ASCENT SPREADING EWD WITH THE GREAT BASIN SHORT WAVE TROUGH IS EXPECTED TO REACH THE CENTRAL PLAINS THIS AFTERNOON…AIDING WITH NEW TSTM DEVELOPMENT AND RE-INTENSIFICATION OF ANY MORNING TSTM ACTIVITY THAT REMAINS ACROSS THIS REGION INTO THE AFTERNOON. GIVEN UNCERTAINTY OF PLACEMENT OF ONGOING MORNING TSTM CLUSTERS/ATTENDANT CLOUDINESS AT 12Z…AND THEIR AFFECTS ON NEW TSTM DEVELOPMENT LATER TODAY…THIS OUTLOOK WILL NOT INCLUDE SEVERE PROBABILITIES GREATER THAN 15%. MODERATE INSTABILITY AND EFFECTIVE BULK SHEAR OF 35-50 KT FROM NEB SWD SUGGESTS THAT SUPERCELLS WILL BE POSSIBLE WITH HAIL AND DAMAGING WINDS. VERY LARGE HAIL MAY OCCUR FROM WRN NEB SWD TO THE OK/TX PANHANDLES WHERE THE COMBINATION OF STRONGEST DEEP LAYER SHEAR/INSTABILITY SHOULD COINCIDE. MODELS SUGGEST LOW LEVEL SHEAR MAY BE SUPPORTIVE FOR A FEW TORNADOES FROM SRN NEB SWD THROUGH WRN
KS/ERN CO TO THE TX PANHANDLE/FAR WRN OK.

GREATER CONFIDENCE EXISTS WITH THE DEVELOPMENT OF ONE OR MORE MCSS THIS EVENING THROUGH TONIGHT AS A SLY LLJ STRENGTHENS OVER THE SRN PLAINS AND KS ACTIVITY EVOLVES/GROWS UPSCALE WITH AN MCS MOVING SSEWD ACROSS TX PANHANDLE/MUCH OF OK INTO N TX BY 12Z FRIDAY. A SECOND MCS MAY TRACK ESEWD ACROSS ERN KS INTO WRN MO.

FARTHER S…A MID LEVEL IMPULSE…EMANATING FROM NRN MEXICO…IS EXPECTED TO MOVE EWD TODAY REACHING SERN NM/SW TX THIS AFTERNOON. ASCENT WITH THIS FEATURE SHOULD SUPPORT TSTM DEVELOPMENT ACROSS THIS REGION. MODERATE INSTABILITY AND SUFFICIENT EFFECTIVE SHEAR WILL SUPPORT ORGANIZED STORMS PRODUCING MAINLY HAIL AND DAMAGING WINDS.

…NRN HIGH PLAINS /WY-MT/…
AS THE UPR LVL RIDGE BEGINS TO BUILD NWD ON THURSDAY…TSTM POTENTIAL WILL LIKELY DECREASE…BUT NOT BE ENTIRELY OUT OF THE FORECAST. A WEAK FRONT IS EXPECTED TO HANG UP ALONG THE HIGHER TERRAIN. ALTHOUGH COMPARATIVELY DRIER THAN PREVIOUS DAYS…A NARROW TONGUE OF MID 40S TO NEAR 50 DEG F SURFACE DEWPOINTS SHOULD RESIDE INVOF THE FRONT. DIURNAL UPSLOPE WINDS AND DIFFERENTIAL HEATING WILL BE THE IMPETUS FOR ISOLATED HIGH BASED TSTMS THIS AFTERNOON/EVENING OVER SRN MT/ERN WY. STRONGER VERTICAL SHEAR IS PROGGED TO BE OVER WY WHERE SUPERCELL STRUCTURES WITH LARGE HAIL MAY OCCUR. OTHERWISE…FARTHER N…ACTIVITY WILL PROBABLY BE LESS ORGANIZED WITH ISOLATED HAIL/GUSTY WINDS.

…DAKOTAS TO UPPER MS VALLEY…
MODELS SUGGEST THE POTENTIAL FOR TSTMS TO DEVELOP ALONG A SURFACE TROUGH MOVING EWD ACROSS ERN SD AND THE UPPER MS VALLEY. WEAK FORCING ALOFT MAY TEND TO LIMIT THE OVERALL DEVELOPMENT OF STRONGER TSTMS. HOWEVER…30-35 KT OF DEEP LAYER SHEAR AND MLCAPE UP TO 1000 J/KG SUGGESTS THAT A FEW STORMS WILL BE SEVERE WITH ISOLATED
HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.

…ERN MA TO NRN NEW ENGLAND…
A MID LEVEL IMPULSE MOVING NEWD ACROSS NRN NEW ENGLAND TODAY WITH COLD MID LEVEL TEMPERATURES /-20 TO -22C/ AND SURFACE HEATING WILL RESULT IN STEEP LAPSE RATES. TSTMS ARE EXPECTED TO DEVELOP BY LATE MORNING/EARLY AFTERNOON AS THIS TROUGH MOVES ACROSS THE REGION…WITH ISOLATED HAIL BEING THE PRIMARY THREAT.

..PETERS/HURLBUT.. 06/19/2008

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z

CURRENT UTC TIME: 0920Z (5:20AM), RELOAD THIS PAGE TO UPDATE THE TIME. If you notice in the graph, Florida has a SEE TEXT box, but you won’t find the corresponding text in the discussion.

I think this is an oops. ;-)