We were in a brief pause right now. About 70 tornadoes touched down on this day a year ago plus many more in the overnight leading into April 27. One person was killed in the evening and five people were killed overnight in Mississippi. The SPC outlook for April 26, 2011:

SPC AC 261234
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0734 AM CDT
TUE APR 26 2011 VALID 261300Z - 271200Z
...THERE IS A HIGH RISK OF SVR TSTMS LATE THIS AFTERNOON INTO
TONIGHT FOR NE TX...FAR SE OK...EXTREME NW LA...AND THE SRN HALF OF
AR... ...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK...FROM
NE TX/SE OK TO THE CONFLUENCE OF THE MS/OH RIVERS...
...THERE IS A SLGT RISK OF SVR TSTMS IN A BROAD SWATH FROM THE SRN
PLAINS EWD/NEWD TO THE MS/OH VALLEYS AND THE LOWER GREAT LAKES...
...DANGEROUS TORNADO AND SEVERE THUNDERSTORM OUTBREAK EXPECTED LATE
THIS AFTERNOON INTO TONIGHT FROM NE TX ENEWD TO THE MS RIVER... ...SYNOPSIS...
AN INITIAL SHORTWAVE TROUGH OVER MO/IL WILL EJECT NEWD TOWARD LOWER
MI TODAY...WHILE AN INTENSE UPSTREAM JET STREAK PROGRESSES ESEWD TO
THE SRN PLAINS BY TONIGHT. MORNING SUBSIDENCE OVER AR /IN THE WAKE
OF THE DEPARTING WAVE/ WILL BE REPLACED BY ASCENT BEGINNING ALONG
THE RED RIVER VALLEY OF N TX/SRN OK LATER THIS AFTERNOON...SPREADING
EWD THIS EVENING INTO SE OK/NE TX AND SRN AR OVERNIGHT. A STRONG
SURFACE CYCLONE WILL DEVELOP EWD ALONG THIS SAME CORRIDOR IN
RESPONSE TO STRONG UPPER DIVERGENCE IN THE LEFT EXIT REGION OF THE
90-100 KT MIDLEVEL JET. THE CYCLOGENESIS WILL ALSO PROMOTE THE
DEVELOPMENT OF A STRENGTHENING SLY/SSWLY LLJ FROM THE ARKLATEX TO
THE LOWER MS VALLEY OVERNIGHT. MEANWHILE...RICH BOUNDARY LAYER
MOISTURE ACROSS E TX...BENEATH A PLUME OF STEEP MIDLEVEL LAPSE RATES
ORIGINATING TO THE W...WILL PROVIDE MODERATE-STRONG WARM SECTOR
INSTABILITY IN ADVANCE OF THE DEVELOPING CYCLONE. THE NET RESULT
WILL BE A STRONGLY SHEARED AND UNSTABLE WARM SECTOR LATE THIS
AFTERNOON INTO TONIGHT...
WHICH APPEARS SUPPORTIVE OF A DANGEROUS
TORNADO AND SEVERE THUNDERSTORM OUTBREAK. ...S/SE AR INTO NW MS TODAY...
INITIAL WARM ADVECTION STORMS WILL FORM DURING THE DAY ALONG AND N
OF THE OUTFLOW/WARM FRONT ACROSS S/SE AR AND NW MS...AS LOW-LEVEL
WAA INCREASES WITH A DEVELOPING LLJ. A FEW SUPERCELLS ARE EXPECTED
ALONG THE WARM FRONT...WHERE MODERATE INSTABILITY AND EFFECTIVE SRH
AOA 200 M2/S2 WILL BE SUPPORTIVE OF A FEW TORNADOES...IN ADDITION TO
LARGE HAIL AND DAMAGING WINDS.
...ARKLATEX/SE OK LATE THIS AFTERNOON INTO EARLY TONIGHT...
OVERNIGHT CONVECTION THAT MOVED OVER AR/NW MS LEFT AN E-W OUTFLOW
BOUNDARY THAT WILL BECOME THE EFFECTIVE WARM FRONT TODAY. FARTHER
S...A WEAKENING MCS OVER SRN LA/MS HAS GENERATED A COLD POOL ACROSS
CENTRAL LA/E TX...BUT AN UNIMPEDED FEED OF LOW 70S BOUNDARY LAYER
DEWPOINTS REMAINS TO THE W OF THIS CONVECTION ACROSS SE TX. THE SE
TX MOISTURE WILL SURGE NWD TODAY AS THE SRN LA STORMS
DISSIPATE...WHILE STEEP MIDLEVEL LAPSE RATES WILL CONTINUE TO
OVERSPREAD THE WARM SECTOR FROM THE W. THESE PROCESSES...COMBINED
WITH DAYTIME HEATING...WILL CONTRIBUTE TO AFTERNOON MLCAPE VALUES OF
2500-3500 J/KG IN THE NE TX WARM SECTOR...WITH SOMEWHAT LESSER
INSTABILITY FARTHER E ACROSS NRN LA/SRN AR...AND FARTHER N INTO SE
OK.
SUPERCELLS ARE EXPECTED TO INITIATE BY MID-LATE AFTERNOON ACROSS
N/NE TX...ALONG THE WARM FRONT AND DRYLINE TO THE IMMEDIATE E/SE OF
THE SURFACE LOW...AND SPREAD EWD TOWARD SW AR/NW LA THROUGH TONIGHT.
THE STRONG INSTABILITY...EFFECTIVE BULK SHEAR IN EXCESS OF 60
KT...EFFECTIVE SRH OF 300-500 M2/S2...
AND A SUFFICIENTLY MOIST
BOUNDARY LAYER WILL BE FAVORABLE FOR LONG-TRACK/DAMAGING TORNADOES
WITH DISCRETE AND CLUSTER SUPERCELLS INTO THE LATE EVENING/EARLY
NIGHTTIME HOURS. VERY LARGE HAIL AND DAMAGING WINDS WILL ALSO BE
LIKELY WITH THE INITIAL SUPERCELLS.
...NRN LA/SE AR/NW MS/WRN TN TONIGHT...
AS THE STRONG SYNOPTIC CYCLONE PROGRESSES EWD AND INTERACTS WITH THE
UNSTABLE WARM SECTOR...INTENSE CONVECTION IS LIKELY THROUGH THE
OVERNIGHT HOURS. INITIAL TORNADIC SUPERCELLS IN NE TX/SW AR AREA
SHOULD EVENTUALLY GROW UPSCALE INTO ONE OR MORE INTENSE
MCS/S...WHICH COULD EVOLVE INTO BOW ECHOES WITH THE POTENTIAL FOR
WIDESPREAD/INTENSE DAMAGING WINDS...AS WELL AS TORNADOES. THIS
ACTIVITY SHOULD PROGRESS QUICKLY EWD/NEWD TO THE MS RIVER LATE
TONIGHT AS THE SYNOPTIC WAVE BEGINS TO EJECT ENEWD.
...OH VALLEY REGION THROUGH EARLY TONIGHT...
THE EJECTING LEAD SHORTWAVE TROUGH WILL PROVIDE A BROAD SWATH OF
MODERATE-STRONG SWLY MIDLEVEL FLOW...ABOVE RESIDUAL BOUNDARY LAYER
DEWPOINTS IN THE UPPER 50S TO LOWER 60S. THE LINGERING CLOUDS AND
RESIDUAL OUTFLOW FROM PRIOR CONVECTION MAKE THE CONVECTIVE EVOLUTION
SOMEWHAT UNCERTAIN TODAY ACROSS THE OH VALLEY REGION...THOUGH
SURFACE-BASED INSTABILITY WILL BE SUFFICIENT FOR A FEW SUPERCELLS
AND/OR BOWING SEGMENTS WITH A RISK FOR A COUPLE OF
TORNADOES...DAMAGING WINDS...AND ISOLATED LARGE HAIL.
..THOMPSON/COHEN.. 04/26/2011
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NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z