SEVERECAST DAY 10 – MIDNIGHT, WEDNESDAY, MARCH 10

…SEVERE THREAT RETURNS TO OKLAHOMA ON WEDNESDAY…

TOUGH FORECAST FOR WEDNESDAY.  THERE ARE SLIGHT DIFFERENCES IN THE EVENING NAM AND GFS WITH REGARD TO THE POSITION OF THE MID LEVEL STORM/SURFACE REFLECTION THAT WILL BE AFFECTING OKLAHOMA.  INTENSE SYSTEM WILL BE LOCATED IN EASTERN NEW MEXICO AT DAY BREAK… SHIFTING EAST NORTHEASTWARD INTO WESTERN OKLAHOMA BY NOON AND NORTHEAST OKLAHOMA BY SUNSET.  THE NAM IS SLIGHTLY FARTHER NORTH WITH THE UPPER LOW THAN THE GFS.  AT THE SURFACE… STRONG PRESSURE FALLS WILL BEGIN AT THE START OF THE DAY OVER WESTERN OKLAHOMA/TEXAS WITH DEEPENING CYCLONE EVOLVING IN CENTRAL OKLAHOMA BY NOON.  GIVEN THE STRENGTH OF THIS SYSTEM… IF RAPID MOISTURE RETURN WERE TO OCCUR… THERE WOULD LIKELY BE A SIGNIFICANT SEVERE WEATHER OUTBREAK IN EASTERN OKLAHOMA.  AT THIS TIME… THERE ARE ENOUGH QUESTIONS REGARDING MOISTURE RETURN TO LIMIT SEVERE POTENTIAL.

STILL, THERE ARE A COUPLE OF AREAS THAT NEED TO BE IDENTIFIED FOR A RISK OF SEVERE STORMS.  FIRST… I WILL ADD MUCH OF NORTHWEST AND NORTH CENTRAL OKLAHOMA WHERE THERE IS ENOUGH EVIDENCE TO SUPPORT AFTERNOON CONVECTION ALONG AND NORTH OF THE MID LEVEL COLD CORE TRACK.  THESE STORMS MAY VERY WELL PRODUCE HAIL TO SEVERE SIZE AND GUSTY WINDS.  TORNADO THREAT IN THIS AREA MAY BE NON-ZERO… BUT DOESN’T WARRANT FORECAST CONSIDERATION AT THIS TIME.  THIS WILL HAVE TO BE RE-EVALUATED IN THE MORNING.

A MORE CONCERNING SEVERE WEATHER THREAT WILL DEVELOP BETWEEN NOON AND 3 P.M. OVER NORTHEAST OKLAHOMA.  MOST MODEL DATA SUGGEST SUFFICIENT LOW LEVEL MOISTURE RETURN TO TAKE PLACE IN THIS AREA TO SUPPORT A MODERATELY UNSTABLE ATMOSPHERE EAST AND NORTHEAST OF THE SURFACE LOW TRACK.  LOW LEVEL AND DEEP LAYER SHEAR SHOULD BE IMPRESSIVE AND MORE THAN ADEQUATE TO SUPPORT ROTATING STORMS WITH THE POTENTIAL FOR SEVERE HAIL… DAMAGING WINDS AND A COUPLE OF TORNADOES.  THE BIGGEST CONCERN IN THIS PART OF THE FORECAST IS THAT IT MAY NEED TO BE SHIFTED NORTHEASTWARD AND POSSIBLY – OUT OF THE STATE.

TRAILING DRYLINE SOUTHWARD THROUGH FAR EASTERN OKLAHOMA ALSO HAS THE POTENTIAL TO GENERATE ISOLATED SEVERE THUNDERSTORMS BY AFTERNOON.  AGAIN… GIVEN THE SHEAR PROFILES… SUPERCELL STORMS WOULD BE POSSIBLE WITH A LARGE HAIL AND ISOLATED TORNADO THREAT.

THE OVERALL CONFIDENCE IN THIS FORECAST IS LOW.  TRACK AND SPEED OF THE UPPER SYSTEM AND THE ASSOCIATED LOW… LOW LEVEL BOUNDARIES AND RETURN OF MOISTURE/INSTABILITY ARE ALL IN QUESTION.  THERE WILL LIKELY BE ADJUSTMENTS MADE DURING THE MORNING HOURS.

ON THIS DATE IN 1986… SEVERE THUNDERSTORMS WERE OBSERVED IN EVERY SECTION OF OKLAHOMA EXCEPT THE PANHANDLE.  THERE WERE 48 REPORTS OF LARGE HAIL AND DAMAGING WINDS.  HAIL REACHED GOLFBALL SIZE IN CLEVELAND, HUGHES, PONTOTOC AND LOVE COUNTIES.

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SEVERECAST DAY 9 – MIDNIGHT, TUESDAY, MARCH 9

…QUIET WEATHER RETURNS TO OKLAHOMA ON TUESDAY…

STRONG UPPER LOW OVER KANSAS AT THE BEGINNING OF THE DAY IS FORECAST TO LIFT NORTHWARD INTO NEBRASKA WITH TROUGH AXIS ROTATING NORTHEASTWARD INTO THE UPPER MIDWEST.

AT THE SURFACE… DEEP LOW PRESSURE NEAR THE KANSAS/OKLAHOMA BORDER WILL SHIFT NORTHEASTWARD – HELPING PUSH WARM/MOIST SECTOR EAST OF THE STATE BY LATE MORNING.

THE ATMOSPHERE ACROSS OKLAHOMA WILL DRY AND STABILIZE THROUGH THE DAY.  A FEW EARLY DAY THUNDERSTORMS ARE POSSIBLE IN THE SOUTHEAST… BUT STORMS SHOULD REMAIN BELOW SEVERE LEVELS.

ON THIS DATE IN 1986… SEVERE THUNDERSTORMS WERE OBSERVED IN EVERY SECTION OF OKLAHOMA EXCEPT THE PANHANDLE.  THERE WERE 48 REPORTS OF LARGE HAIL AND DAMAGING WINDS.  HAIL REACHED GOLFBALL SIZE IN CLEVELAND, HUGHES, PONTOTOC AND LOVE COUNTIES.

SEVERECAST DAY 8a – 9:00 A.M., MONDAY, MARCH 8

…SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON IN WESTERN OKLAHOMA…

MINOR CHANGES WERE MADE TO THE ONGOING FORECAST.  THE OVERALL LEVEL ONE THREAT AREA DIDN’T CHANGE MUCH… BUT THE THREAT FOR ISOLATED SUPERCELL STORMS HAS SHIFTED A LITTLE TO THE NORTHWEST.

12Z NAM MOVES THE STRONG UPPER LOW FROM ARIZONA THIS MORNING TO CENTRAL KANSAS BY SUNRISE TUESDAY.  RUC AND NAM BOTH SUGGEST RAPID DEEPENING OF SURFACE CYCLONE OVER THE OKLAHOMA PANHANDLE/EXTREME SOUTHWEST PART OF KANSAS BY THIS AFTERNOON.  THE TERM WARM SECTOR CAN BE USED LOOSELY AS EXTENSIVE CLOUD COVER/FOG AND LIGHT PRECIPITATION HAS HELD TEMPERATURES DOWN IN THE 40S AND 50S.  HOWEVER… MORNING UPPER AIR DATA SHOWS THAT THE WARM SECTOR HAS BECOME INCREASINGLY MOIST OVER THE PAST 24 HOURS.

WIDESPREAD THUNDERSTORM ACTIVITY HAS BEEN BREAKING OUT OVER THE LAST FEW HOURS IN WESTERN TEXAS AND THE OKLAHOMA PANHANDLE AS STRONG LIFTING ASSOCIATED WITH THE UPPER STORM ADVANCES EASTWARD.  THESE STORMS SHOULD CONTINUE TO EXPAND IN COVERAGE AND MOVE QUICKLY NORTHEASTWARD ACROSS THE STATE.

IF AN ORGANIZED THREAT OF SEVERE WEATHER EVOLVES THIS AFTERNOON… IT WILL MOSTLY LIKELY HAVE TO BE BEHIND THIS CURRENT WAVE OF STORMS/PRECIPITATION.  SKIES WILL NEED TO CLEAR AND SURFACE HEATING WILL NEED TO TAKE PLACE WITH A NARROW AREA EAST OF THE DRYLINE HAVING THE POTENTIAL TO BECOME MODERATELY UNSTABLE.

THE POTENTIAL FOR SUPERCELL STORMS IN THIS FORECAST WAS SHIFTED NORTHWESTWARD WHERE NOSE OF AFTERNOON INSTABILITY IS EXPECTED TO COEXIST WITH A STRONG AMOUNT OF LOW LEVEL SHEAR JUST SOUTHEAST OF THE DEEPENING SURFACE LOW.  HERE… LOW TOPPED SUPERCELLS MAY PRODUCE SEVERE SIZE HAIL ALONG WITH THE THREAT FOR SHORT-LIVED TORNADOES.

 

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SEVERECAST DAY 8 – MIDNIGHT, MONDAY, MARCH 8

…FIRST SEVERE STORMS OF THE SEASON POSSIBLE TODAY…

…BLOG MACHINE ATE THE WONDERFUL POST I PUT UP YESTERDAY ON THE 7TH…

MODELS ARE IN GENERAL AGREEMENT IN BRINGING UPPER LOW LOCATED OVER WESTERN ARIZONA AT THIS HOUR… RAPIDLY EAST NORTHEASTWARD TOWARD THE OKLAHOMA PANHANDLE/SOUTHEAST COLORADO BY EARLY EVENING ON MONDAY.  IMPRESSIVE HEIGHT FALLS OF GREATER THAN 100 METERS AND 500 MB WINDS OF OVER 70 KTS WILL BE ASSOCIATED WITH THE SYSTEM – THE BIGGEST SURGE BEING THROUGH WESTERN OKLAHOMA.

AT THE SURFACE… THE MODELS START TO SEPARATE WITH REGARD TO HOW FAST THE CYCLONE DEEPENS.  THE GFS IS FASTER TO DO SO OVER SOUTHWEST KANSAS WITH A STRONG DRY SLOT SURGING EASTWARD ACROSS THE TEXAS PANHANDLE INTO WESTERN OKLAHOMA.

BEFORE THIS ARRIVES… WIDESPREAD SHOWERS AND STORMS ARE EXPECTED TO FORM IN STRONG WARM AIR ADVECTION ZONE ACROSS WESTERN TEXAS AT DAYBREAK – AND THEN MOVING RAPIDLY NORTHEASTWARD ACROSS THE STATE DURING THE MORNING AND AFTERNOON.  THERE MAY BE ENOUGH ELEVATED INSTABILITY TO SUPPORT SOME HAIL PRODUCING STORMS WITH THIS EARLY BATCH… BUT HAIL SIZE SHOULD REMAIN NEAR OR BELOW SEVERE LEVELS.

BEHIND THIS INITIAL SURGE OF STORMS… SKIES SHOULD BEGIN TO CLEAR AND SURFACE HEATING WILL BE TAKING PLACE NEAR THE DRYLINE ACROSS WESTERN OKLAHOMA.  AGAIN… IT REMAINS TO BE SEEN AT THIS TIME AS TO HOW SHARP THE DRYLINE WILL BE AND WHERE IT WILL BE LOCATED BY MID TO LATE AFTERNOON.  AT LEAST SOME OF THE DATA SUGGESTS THAT THERE WILL BE A NARROW AXIS OF 500 TO 1000 J/KG MLCAPE THAT FORMS JUST AHEAD OF THE DRYLINE IN WESTERN OKLAHOMA.  IF SUBSISTENCE BEHIND THE WAVE OF FIRST STORMS WERE TO RELAX… THE ATMOSPHERE BECOME MODERATELY UNSTABLE… AND A SHARP DRYLINE EVOLVE IN WESTERN OKLAHOMA… THE STAGE WOULD BE SET FOR A LATE AFTERNOON ROUND OF LOW TOPPED THUNDERSTORMS TO DEVELOP.  THESE WOULD LIKELY BE SUPERCELLULAR IN NATURE WITH THE POTENTIAL TO PRODUCE SEVERE HAIL AND A TORNADO OR TWO.

THIS FORECAST IS HIGHLY CONDITIONAL ON ALL OF THESE EVENTS COMING TOGETHER… AND AT THIS TIME I WILL ELECT TO BUY INTO THIS SOLUTION – INTRODUCING A RISK OF SEVERE THUNDERSTORMS OVER WESTERN OKLAHOMA.  THE MORE LIKELY EVENT WOULD BE A LEVEL ONE THREAT WITH ISOLATED REPORTS OF HAIL NEAR ONE INCH.  HOWEVER… AN IDEAL SITUATION WOULD PRODUCE SOME LOW-TOPPED SUPERCELL EVENTS WHICH ARE ALSO CAPABLE OF SHORT-LIVED TORNADOES.  AT THE SITUATION EVOLVES DURING THE LATE MORNING AND EARLY AFTERNOON… THIS FORECAST WILL LIKELY HAVE TO BE ADJUSTED.  THE MOST LIKELY ADJUSTMENT WOULD BE A DOWNWARD TREND IN THREAT LEVEL.  ONLY MINOR ADJUSTMENTS WOULD LIKELY NEED TO BE MADE IN THE THREAT AREA…

ON THIS DATE IN 1974… THERE WERE ONLY A COUPLE OF REPORTS OF SEVERE WEATHER… BUT ONE WAS A WEAK TORNADO THAT TRACKED THROUGH PARTS OF OKLAHOMA CITY.  THE GREATEST AMOUNT OF DAMAGE OCCURRED AT NORTHEAST 19TH AND EASTERN WHERE ONE PERSON SUSTAINED MINOR INJURIES.

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SEVERECAST DAY 6 – MIDNIGHT, SATURDAY, MARCH 6

…ANOTHER THUNDERLESS DAY EXPECTED… CHANGES BEGIN SUNDAY…

AN UPPER LEVEL LOW PRESSURE AREA WILL MOVE OUT OF NEBRASKA TODAY TOWARD WESTERN IOWA.  A LARGE UPPER STORM WILL BE MOVING TOWARD THE SOUTHWEST U.S… APPROACHING SOUTHERN CALIFORNIA AND SOUTHWEST ARIZONA.  IN BETWEEN… OKLAHOMA WILL BE UNDER THE INFLUENCE OF SHORT WAVE RIDGING AND ANOTHER DAY OF QUIET WEATHER.  TEMPERATURES WILL ONCE AGAIN BE SEASONABLY WARM AND THERE WILL BE A PERIOD DURING THE AFTERNOON WHERE WINDS ARE GUSTY FROM THE SOUTHWEST.

A WEAK COLD FRONT WILL SLIDE INTO THE PANHANDLE AND EXTREME NORTHWEST BY DAYBREAK ON SUNDAY.  IT SHOULDN’T MOVE TOO FAR INTO OKLAHOMA BEFORE BECOMING STATIONARY.  LIMITED MOISTURE AND MID LEVEL CAPPING WILL KEEP THIS FRONT DRY.

BY SUNDAY MORNING… WIDESPREAD THUNDERSTORMS WILL HAVE FORMED IN AN AREA OF STRONG WARM AIR ADVECTION OVER WESTERN TEXAS.  THERE IS A CHANCE THAT THESE WILL BE APPROACHING SOUTHWEST OKLAHOMA BY SUNRISE… BUT ARE NOT EXPECTED TO HAVE ENTERED THE STATE BY THEN.

ON THIS DATE IN 1990… SCATTERED SEVERE THUNDERSTORMS PRODUCED HAIL ACROSS THE STATE.  THE LARGEST HAIL WAS AROUND GOLFBALL SIZE IN NORMAN.

SEVERECAST DAY 5 – MIDNIGHT, FRIDAY, MARCH 5

…FORECAST REMAINS DRY… THUNDER CHANCES INCREASE BY LATE IN UPCOMING WEEKEND…

LATEST RUN OF SREF INDICATES THAT A BITE WILL BE TAKEN OUT OF THE GREAT PLAINS UPPER RIDGE BY A SMALL BUT STRONG STORM SYSTEM THAT WILL MOVE OUT OF COLORADO INTO THE CENTRAL PLAINS.  THERE ARE INDICATIONS THAT STORMS WILL FORM BY LATE IN THE AFTERNOON OVER WESTERN KANSAS AND NEBRASKA… BUT THESE WILL BE ASSOCIATED WITH THE STRONG LIFTING EAST OF THE UPPER LOW WHICH WILL REMAIN NORTH OF THE STATE.

FOR OKLAHOMA… THE ONLY SIGNIFICANT IMPACTS WILL BE TO MAINTAIN GUSTY SOUTH WINDS… SEASONABLY MILD TEMPERATURES AND A VERY SLOW INCREASE IN MOISTURE.

MOST MODEL DATA SUGGESTS AN INCREASED RISK OF THUNDERSTORMS – AND AT LEAST A LOW THREAT OF SEVERE THUNDERSTORMS – BEGINNING ON SUNDAY AND CONTINUING THROUGH MONDAY.

ON THIS DATE IN 1961… FOUR TORNADOES WERE REPORTED IN OKLAHOMA.  ONE TORNADO HIT A BOWLING ALLEY IN PAULS VALLEY INJURING ONE PERSON AND CAUSING $250,000 DAMAGE.

SEVERECAST DAY 4 – MIDNIGHT, THURSDAY, MARCH 4

…SLIGHTLY WARMER… BUT STILL DRY…

A BROAD UPPER LEVEL TROUGH IS CURRENTLY FOUND OVER THE EASTERN U.S… A RIDGE OF HIGH PRESSURE IS LOCATED OVER THE PLAINS AND A COMPACT BUT STRONG STORM SYSTEM IS MOVING THROUGH CALIFORNIA/NEVADA.

AS THE WESTERN SYSTEM ADVANCES EASTWARD INTO UTAH AND ARIZONA DURING THE AFTERNOON ON THURSDAY… SURFACE PRESSURES WILL BEGIN FALLING ACROSS THE WESTERN PLAINS.  WINDS WILL BECOME QUITE GUSTY OUT OF THE SOUTH AND A DECENT WARMUP WILL BE UNDERWAY.

LOW LEVEL MOISTURE WILL BE SLOW TO RETURN AND THE ATMOSPHERE WILL REMAIN TOO STABLE TO SUPPORT THUNDERSTORMS ON THURSDAY… DESPITE INCREASING LIFTING APPROACHING THE PANHANDLE BY LATE IN THE EVENING.

ON THIS DATE IN 2004… A SIGNIFICANT SEVERE WEATHER OUTBREAK AFFECTED MOST OF THE SOUTHEAST HALF OF OKLAHOMA.  THERE WERE NEARLY 70 REPORTS OF DAMAGING WINDS – SOME OVER 80 MPH – AS WELL AS REPORTS OF LARGE HAIL AND ONE WEAK TORNADO NEAR MULDROW.  THE TORNADO WAS ONLY RATED F0 AND WAS LESS THAN TWO MILES LONG.  A CARPORT AND BARN WERE DESTROYED.  WHILE THE EVENT WAS MINOR… IT DID END A STRING OF 292 DAYS WITHOUT A TORNADO IN THE STATE.

SEVERECAST DAY 3 – MIDNIGHT, WEDNESDAY, MARCH 3

… NO THUNDERSTORMS EXPECTED ACROSS THE STATE TODAY…

THROUGH THE DAY… A LARGE UPPER LOW/TROUGH OF LOW PRESSURE WILL BE MOVING OFF THE EAST COAST WHILE AN UPPER RIDGE BUILDS INTO THE PLAINS.  A SMALL BUT STRONG UPPER STORM WILL BE MOVING INTO NORTHERN CALIFORNIA.

FOR OKLAHOMA… THE ATMOSPHERE WILL REMAIN DRY AND STABLE.

ON THIS DATE IN 1944… A TORNADO STRUCK NEAR HUGO, OKLAHOMA… DESTROYING 50 HOMES AND INJURING EIGHT PEOPLE.  “THE TORNADO, WHICH EYEWITNESSES SAY BROKE FOUR MILES WEST OF HUGO, WENT NORTHEAST AND THREE MILES EAST, THEN CIRCLED AND CAME INTO HUGO FROM THE SOUTH, PRODUCED ITS FREAKS.  A BEAR, BELONGING TO THE AL G. KELLY CIRCUS, WINTERING THREE MILES EAST OF HUGO, WHICH WAS STAKED OUT, WAS FOUND AFTER THE STORM SUBSIDED, WEARING A PAIR OF PANTS, EATING FROM A JAR OF JELLY.”

SEVERECAST DAY 2 – MIDNIGHT, TUESDAY, MARCH 2

…CONTINUED QUIET WEATHER ACROSS THE STATE…

UPPER SYSTEM IN THE GULF OF MEXICO WILL MOVE EASTWARD TOWARD FLORIDA DURING THE DAY.  THERE WILL BE AN EMBEDDED VORT MAX OVER THE NORTHERN PLAINS DIVING SOUTHWARD TOWARD THE STATE WHILE HIGH PRESSURE EDGES EASTWARD THROUGH THE ROCKIES.  THE ATMOSPHERE OVER OKLAHOMA WILL REMAIN DRY AND STABLE THROUGH THE PERIOD.

BY MORNING WEDNESDAY… THE NEXT STORM TO AFFECT THE STATE WILL BE APPROACHING NORTHERN CALIFORNIA.

ON THIS DATE IN 1977… A SMALL SEVERE WEATHER OUTBREAK PRODUCED SEVERAL TORNADOES OVER SOUTHERN AND WESTERN OKLAHOMA.  ONE OF THE TORNADOES WAS AN F3 IN STEPHENS COUNTY THAT WAS OVER FOUR MILES LONG AND UP TO 200 YARDS WIDE.  THE TORNADO INJURED ONE PERSON.

SEVERECAST DAY 1 – MIDNIGHT, MONDAY, MARCH 1

…QUIET START TO THE THUNDERSTORM SEASON…

TONIGHT… A STRONG UPPER STORM SYSTEM IS FOUND OVER WESTERN TEXAS WHICH WILL MOVE SOUTHEAST TOWARD THE LOWER MISSISSIPPI VALLEY DURING THE NEXT 24 HOURS.  DURING THE SAME PERIOD… A STRONG RIDGE OF HIGH PRESSURE BUILDS EASTWARD THROUGH THE ROCKIES WHILE SEVERAL STORMS IN THE PACIFIC ARE SETTING THEIR EYES ON THE WEST COAST.

THE SURFACE REFLECTION OF THE TEXAS SYSTEM WILL BE LOW PRESSURE THAT WILL MIGRATE EASTWARD ALONG THE GULF COAST.  THIS FEATURE WILL EFFECTIVELY CUT OFF ANY NORTHWARD RETURN OF LOW LEVEL MOISTURE AND HIGH PRESSURE WILL SETTLE IN OVER THE STATE.

THERE MAY BE SOME LIGHT RAIN OR A RAIN/SNOW MIX ALONG THE RED RIVER DURING THE DAY… BUT LACK OF SUFFICIENT INSTABLITY PRECLUDES A FORECAST OF THUNDER.

ON THIS DATE IN 1988… SEVERE THUNDERSTORMS BECAME QUITE NUMEROUS ACROSS SOUTHERN AND EASTERN OKLAHOMA.  HAIL GENERALLY AROUND THE SIZE OF QUARTERS OR SMALLER WAS COMMON… BUT DID REACH GOLFBALL SIZE IN COTTON AND COMANCHE COUNTIES.

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Okarche, Oklahoma