Severe Weather Threat thru Mar 1

Sat Feb 22 Convective Outlook
Storm Prediction Center Norman Ok
No Svr Tstm Areas Forecast...

Upper-Air Pattern This Period Will Be Characterized By Hudson Bay
Vortex...Leading Broadly Cyclonic Flow Across Great Majority Of
Conus.

That Flow Will Be Interspersed With Very Low-Amplitude Perturbations And Accompanying/Elongated Vorticity Banners...But No
Substantial Shortwaves.

At Sfc...Frontal Zone Associated With Hudson Bay Vortex Has Stalled
From Central Fl Peninsula Wswwd Across Central Gulf.

Frontolysis Is Fcst Over Wrn Gulf While Middle-Ern Gulf And Fl Segments Weaken And Retreat Nwd More Slowly.

Separate Area Of Sfc Baroclinicity Over Tx Panhandle...Ok And Ar Will Remain Displaced From Convective Potential Day-1.

Central Gulf Coast And Lower Delta Regions...

Scattered Tstms Are Fcst To Develop Overnight -- Mainly After 6z --
Increasing In Coverage As Regime Spreads/Shifts Ewd Along La/Ms/Al Coasts Toward Wrn Fl Panhandle.

Most Vigorous Cells May Offer Hail Near Svr Limits...However Threat Appears Too Mrgl/Isolated For Categorical Risk.

Tonight...Low-Level Trajectories From S Of Front Should Begin To
Advect Convectively Supportive Moisture Over Relatively Stable / Low-Thetae Boundary Layer Near Coast.

Moist Fetch Should Saturate Soundings In 850-900 Mb Layer... Beneath Sufficiently Steep Midlevel Lapse Rates To Promote 500-1000 J/Kg Mucape...Locally Higher. Parcels Will Be Lifted Isentropically To Resulting Lfc...Amidst Effective Shear Magnitudes Mostly In 30-40 Kt Range.

Fl Peninsula...

Widely Scattered To Scattered Tstms Are Expected Today In Clusters.

A Few Of These Tstms May Produce Stg Gusts...However Overall
Intensity/Organization Of Wind Risk Will Be Limited By Lack Of More
Robust Shear/Buoyancy Values.

Moisture-Channel Imagery And Most Progs Indicate No Substantial Upper-Air Support Or Suppression Of Convective Potential...Which Will Be Driven Mainly By Areas Of Low-Level Lift.

Sfc Frontal Zone...Along With Sea Breezes...Differential-Heating Lines And Outflow Boundaries S Of Front...Will Be Primary Foci For Convective Initiation.

Aside From Ongoing Convection Over Central Fl...Tstms Should Form This Aftn...As Diurnal/Diabatic Heating Acts On Those Boundaries In Presence Of Weak Cinh.

That Heating With Sfc Dew Points Upper 60s/Lower 70s F Should Be Sufficient To Offset Small Lapse Rates Aloft For Mlcape To Reach 1000-1500 J/Kg Range.

Weak Low-Level Wind Speeds Will Keep Hodographs Small... Though 60-70 Kt Anvil-Level Wlys Should Aid In Venting Upper Reaches Of Tstms.

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Sun Feb 23 Convective Outlook
Storm Prediction Center Norman Ok
No Svr Tstm Areas Forecast...

Fast Nwly Flow Aloft Will Remain Across Much Of The Conus With A
Large Upper-Low Centered Over Nrn Quebec.

At The Surface...High Pressure Will Be Reinforced Over The Cntrl And Ern States With A Cold Front Sinking Swd Affecting The Srn Plains... Lower Ms Valley And Srn Appalachians By 00z.

S Of This Front...A Relatively Weak Attempt At Moisture Return Will Result In Lower 60s F Surface Dewpoints Across The Gulf Coast Area With A Slight Threat Of Thunderstorms.

Srn La/Ms/Al/Ga And Fl...

Wswly Flow At 850 Mb Will Result In Weak Isentropic Lift And
Advection Of Weak Instability Across The Gulf Coast States Through
The Period.

Scattered Rain And Storms Are Expected To Train Along A Generally W-E Zone Mainly Over Srn Al...Ga...And Nrn Fl.

Despite Strong Mid To Upper-Level Wind Shear...Speeds In The Lowest Few Km Will Not Be Very Strong...And Instability Will Be Weak...Suggesting Any Wind Gusts Will Be Sub-Severe.

To The E...Strong Heating Will Lead To A Diurnal Cu Field Over Much
Of Fl...But Temperatures Aloft Will Be Warm.

Still...Weak Swly Low-Level Flow Will Enhance Convergence Across The Cntrl And Ern Peninsula Resulting In Isolated Non-Severe Thunderstorms During The Day.

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Mon Feb 24 Convective Outlook
Storm Prediction Center Norman Ok
No Svr Tstm Areas Forecast...

A Nwly Flow Regime Aloft Will Persist Across Much Of The Cntrl And
Ern Conus With An Expansive Midlevel Jet Core Extending From The Nrn Plains Into The Ne.

At The Surface...A High Pressure Ridge Will Extend From Mt Sewd Across The Midwest And Into The Mid Atlantic...Providing Cool And Dry Conditions.

To The S...A Stalled Front Will Stretch From Cntrl Tx Ewd Across The
Srn Gulf Coast States.

Weak Instability Will Exist Due To Moisture Near This Boundary...With Sporadic Thunderstorms Possible At Times From The Red River Valley Into The Lower Ms Valley.

Elsewhere...Weak Diurnal Thunderstorms Will Again Be Possible Over Ern Fl.

Red River Valley Into Lower Ms Valley...

Weak Warm Advection Atop The Sfc Front Will Occur Throughout The
Period With Only Minor Ripples In The Flow Aloft In An Otherwise
Broadly Cyclonic Flow Regime.

However...Lift Is Expected To Gradually Increase Overnight Monday In Response To Subtle Height Falls With An Amplifying Trough Diving S Out Of Canada.

While The Nam Forecast Of Elevated Instability Is Likely Too High... There May Be Enough For Isolated Thunderstorms Across The Red River Valley...Then Spreading Ewd Into The Lower Ms Valley Overnight.

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Feb 25-Mar 1 Convective Outlook
Storm Prediction Center Norman Ok

A Persistent Area Of Cyclonic Flow Aloft Will Remain Over Ern Canada
And The Nern United States Through The Period With Upper Low
Centered Over Hudson Bay.

This Pattern Will Also Shunt Substantive Moisture And Instability Well Offshore From D5 Onward With Little Chance Of Any Severe Storms.

For Tue/D4...A Few Weak Storms Will Be Possible From The Lower Ms Valley Ewd Into Fl As The Influences Of An Amplifying Upper Trough To The N Are Felt With A Passing Cold Front.

Models Do Show The Potential For Lower-Latitude Shortwave Troughs Affecting The Srn Tier Of States In The D6-D8 Period.

These Waves May Result In Showers And Weak Thunderstorms Affecting Primarily Gulf Coastal Areas...But Potential Is Low For Severe Storms...As Is Predictability.


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