Omaha, NE
A view from Creighton University in Omaha, NE earlier today showed fairly quiet conditions, however, Omaha is under a SLIGHT RISK of severe weather today! Heavy rain and strong/severe thunderstorms may be possible across parts of the Midwest/Plains through the evening hours. Hail and high wind look to be the primary threat, but this could be some of the first severe weather since late last fall for some of these areas.
See the latest webcam view from Creighton University HERE:
Severe Threat Wednesday
…WRN OK/KS/NEB/IA/MN THIS AFTERNOON INTO EARLY TONIGHT…
THE COLD FRONT /TRAILING THE PRIMARY NRN PLAINS CYCLONE/ WILL MOVE
SEWD ACROSS NEB/SD/IA/MN TODAY…AND ACROSS KS/MO TONIGHT.
LOW-LEVEL MOISTURE WILL BE DRAWN NWD FROM OK/TX IN ADVANCE OF THE
FRONT…WITH THE WRN EDGE OF THE MOIST SECTOR DEMARCATED BY A LEE
TROUGH/DRYLINE EXTENDING SWD FROM A SECONDARY/LEE CYCLONE IN WRN KS
THIS AFTERNOON. THE LOW-LEVEL MOISTURE FIELD HAS BEEN DISRUPTED
ACROSS OK AS A RESULT OF OVERNIGHT CONVECTION…SO NWD MOISTURE
TRANSPORT WILL LIKELY BE DELAYED/REDUCED SOME COMPARED TO THE MORE
AGGRESSIVE MODEL FORECASTS. THIS WILL LIKEWISE REDUCE BUOYANCY FROM
EARLIER EXPECTATIONS…THOUGH MLCAPE OF 1000-2000 J/KG IS STILL
PROBABLE GIVEN THE PLUME OF 8-9 C/KM MIDLEVEL LAPSE THAT HAS
OVERSPREAD THE CENTRAL PLAINS.
THUNDERSTORM INITIATION IS EXPECTED ALONG THE COLD FRONT BY 21-00Z
FROM SW MN SWWD INTO NEB…WITHIN THE NARROW CORRIDOR OF MODERATE
BUOYANCY. GIVEN DEEP-LAYER SHEAR THAT WILL BE MARGINAL FOR
SUPERCELLS…AND SHEAR VECTOR ORIENTATIONS PARALLEL TO THE
BOUNDARY…A RATHER QUICK UPSCALE GROWTH TO LINEAR CONVECTION IS
LIKELY. A FEW DAMAGING GUSTS AND LARGE HAIL WILL BE POSSIBLE WITH
THE STRONGER EMBEDDED STORMS FOR A FEW HOURS LATE THIS AFTERNOON
THROUGH LATE EVENING. FARTHER SW…THE DEGREE OF STORM DEVELOPMENT
IS UNCLEAR ALONG THE DRYLINE THIS AFTERNOON FROM SW KS SWD NEAR THE
TX/WRN OK BORDER. DEEP MIXING WILL PROBABLY REDUCE BOUNDARY LAYER
DEWPOINTS E OF THE DRYLINE…AND THE MOISTURE INFLUX MAY ALSO BE
INTERRUPTED BY THE ONGOING CONVECTION IN N TX. GIVEN THE LIKELY
HIGH-BASED NATURE OF ANY STORMS THAT FORM…AND ONLY
MARGINALLY-FAVORABLE WIND PROFILES FOR SUPERCELLS…WILL MAINTAIN
ONLY 5% HAIL/WIND PROBABILITIES.
…TX TO ERN OK/WRN AR/MO TODAY…
CLUSTERS OF THUNDERSTORMS SHOULD PERSIST AND DEVELOP NEWD THROUGH
THE DAY IN ASSOCIATION WITH THE SUBTLE SPEED MAXIMA AND THE MCV
EJECTING NEWD FROM NE OK. LAPSE RATES ARE NOT AS STEEP AS
YESTERDAY…AND VERTICAL SHEAR HAS ALSO WEAKENED. STILL… REMNANT
INSTABILITY AND SEVERAL CLUSTERS OF STORMS SUGGEST A MARGINAL
WIND/HAIL RISK WITH THE STRONGER EMBEDDED STORMS. AREAS FARTHER S
INTO CENTRAL TX MAY HAVE SOME RISK FOR STRONG STORMS LATER
TODAY…THOUGH CLOUDS WILL TEND TO SLOW SURFACE HEATING. THIS AREA
MAY NEED TO BE RE-EVALUATED IN LATER UPDATES.
…SE GA/NE FL THIS AFTERNOON…
A SHORTWAVE TROUGH OVER NE AL/CENTRAL GA WILL MOVE ESEWD THROUGH
THIS AFTERNOON…BRUSHING THE NE FL/SE GA AREA. THE 12Z JAX
SOUNDING SHOWS SUFFICIENT VERTICAL SHEAR AND POTENTIAL BUOYANCY TO
SUPPORT A RISK FOR ISOLATED DAMAGING GUSTS AND MARGINALLY SEVERE
HAIL FOR A FEW HOURS THIS AFTERNOON.
Severe Threat Thursday
…INDIANA/OH WSWWD ACROSS THE OZARKS…
CONVECTION IS PROGGED TO BE ONGOING AT THE START OF THE PERIOD INVOF
THE ADVANCING COLD FRONT FROM THE UPPER GREAT LAKES REGION SWWD INTO
THE MO VICINITY…WHICH — COMBINED WITH ASSOCIATED CLOUDINESS —
SHOULD ACT TO HINDER DAYTIME HEATING TO SOME DEGREE ACROSS THE WARM
SECTOR. STILL…WITH CONTINUED ENEWD SPREAD OF HIGHER THETA-E
LOW-LEVEL AIR ACROSS THE MIDWEST AHEAD OF THE FRONT…EVEN MODEST
HEATING WILL HELP BOOST MIXED-LAYER CAPE VALUES INTO THE 500 TO 1000
G/KG RANGE ACROSS MUCH OF THE OH VALLEY…AND 1000 TO 2000 J/KG INTO
THE OZARKS WHERE GREATER HEATING AND STEEPER LAPSE RATES ALOFT ARE
EXPECTED.
WITH WEAK SHORT-WAVE TROUGHING EMBEDDED WITHIN THE BROADER CYCLONIC
FLOW FIELD ALOFT EXPECTED TO CROSS THE OH VALLEY DURING THE
AFTERNOON…EXPECT AN INCREASE IN CONVECTION/STORMS INVOF THE
ADVANCING COLD FRONT. DESPITE AFOREMENTIONED LIMITATIONS
THERMODYNAMICALLY…MODERATELY STRONG/VEERING FLOW WITH HEIGHT
ACROSS THE AREA WILL SUPPORT STORM ORGANIZATION — AND ASSOCIATED
RISK FOR ISOLATED HAIL AND LOCALLY DAMAGING WINDS ACROSS THE SLIGHT
RISK AREA. THE ONSET OF A GRADUAL DIURNAL DECREASE IN CONVECTIVE
INTENSITY IS FORECAST DURING THE EVENING ACROSS THE AREA…THOUGH
SEVERE RISK MAY LINGER WELL INTO THE EVENING ACROSS THE OZARKS
VICINITY AS A SECOND VORT MAX ALOFT SHIFTS INTO THIS REGION.
Severe Threat Friday
…OH VALLEY/CENTRAL APPALACHIANS WSWWD INTO SRN AND ERN TX…
ONGOING CONVECTION ACROSS THE OH VALLEY REGION INVOF THE
AFOREMENTIONED COLD FRONT IS FORECAST TO DEVELOP SWWD ACROSS THE TN
AND LOWER MS VALLEYS DURING THE AFTERNOON…AS THE FRONT ADVANCES
INTO A MOIST/DESTABILIZING AFTERNOON AIRMASS. AS STORMS DEVELOP AND
INGEST MOIST/UNSTABLE LOW-LEVEL AIR…STRENGTHENING MID-LEVEL WLYS
ACROSS THE REGION SUGGEST LIKELIHOOD FOR STORM ORGANIZATION WITHIN A
FAVORED CORRIDOR FROM THE TN/KY AREA WSWWD ACROSS THE LOWER MS
VALLEY. HERE…POTENTIAL FOR LOCALLY DAMAGING WINDS AND HAIL IS
EVIDENT WITH STRONGER STORMS…LASTING INTO THE EVENING HOURS. MORE
ISOLATED STORMS WILL BE POSSIBLE ACROSS SERN AND INTO SRN TX —
WHERE A WEAKER KINEMATIC BUT MORE FAVORABLE THERMODYNAMIC
ENVIRONMENT APPEARS SUPPORTIVE OF A LIMITED-COVERAGE SEVERE RISK
THAT MAY LINGER INTO THE OVERNIGHT HOURS.
National Weather Outlook
As our storm system moves southeast through the middle part of the country, thunderstorms will produce heavy rainfall over a couple/few day period. It appears the heaviest rain will fall along and east of the Mississippi River Valley through the early weekend timeframe. Also note the snow potential across the Rockies/Front Range through Friday, where some accumulations will be possible.
Precipitation Outlook.
According to NOAA’s HPC, the rainfall potential through AM Saturday suggests nearly 1″ to 3″+ possible from near the Middle Mississippi Valley to parts of the Northeast. Keep in mind that some of these areas saw nearly 4″ to 7″+ precipitation during the month of March, so the ground is fairly saturated and flooding may be possible.
Thanks for checking in and have a great rest of your week! Don’t forget to follow me on Twitter @TNelsonWX
