Tornado Threat Forecast – Mar 19-25, 2012

NOTE: Our POTENTIAL category has been adjusted to better balance the wording with the true risk. Please visit our Forecast FAQ page for the updated descriptions.

1-3 DAY

Monday

Southern and eastern Plains, western Midwest — POTENTIAL: High — CONFIDENCE: High
Today is primed for tornadic activity ahead of a strong disturbance, with a tornado outbreak possible in the southern half of the risk area. Texas is at the greatest risk today as moderate/high instability and moderate to strong wind shear combine ahead of an advancing cold front. Multiple rounds of storms are expected in the southern Plains now through the overnight hours. Strong forcing within a zone of 500-1000 J/kg CAPE could allow for isolated tornadoes from Missouri to the northern tip of the risk area.

Tuesday

ArkLaTex, southwestern Midwest — POTENTIAL: High — CONFIDENCE: High
Storms with tornadic potential will continue tomorrow as the upper-level trough stalls over the southern Plains. Heavy rain and cloud cover will limit the instability, but the upper-level forcing should be enough to generate a few tornadoes. In addition to the lack of instability, the winds will be backing aloft to a degree, limiting the updraft rotation.

Wednesday

Southern Delta, central Plains — POTENTIAL: Medium — CONFIDENCE: Normal
Strong dynamics will be the main player on Wednesday, with low to moderate instability aiding in storm development in the southern Delta. Very high helicity values ahead of a potent upper-level vort. max will allow for rotation in convective storms. While CAPE is extremely limited north of Louisiana, the strong dynamics will only need a little CAPE to introduce tornadic potential in the northern portions of the risk area.

4-7 DAY

Thursday

Southern Plains, Southeast, southern Midwest — POTENTIAL: Medium — CONFIDENCE: Normal
A cold-core low setup will be present in the southern Plains, with moderate to strong wind shear and enough CAPE to initiate storms with tornadic potential during the afternoon and evening. Further east, storms along and ahead of the cold front will still be able to produce an isolated tornado or two as the front pushes eastward. Timing and placement of the tornado risk areas start to lower confidence by Thursday.

Friday

Southeast, Tennessee Valley — POTENTIAL: Low — CONFIDENCE: Low
An isolated tornado or two are possible on Friday as the main disturbance pushes eastward. Some CAPE will be present ahead of an area of moderate upper-level forcing, but low-level wind shear will not be that favorable.

Saturday

Southeast, Mid-Atlantic, California — POTENTIAL: Low — CONFIDENCE: Low
The eastern U.S. will suffer from similar limitations as Friday, with less confidence in the progression of the storm system. A potent upper-level low will push into California on Saturday, with enough dynamics and wind shear to introduce a low risk area.

Sunday

No tornadic activity expected.