Oct 12, 2018 0600 UTC Day 1 Convective Outlook
Updated: Fri Oct 12 05:42:31 UTC 2018 (20181012 1200Z Day 1 shapefile | 20181012 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20181012 1200 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 97,418 2,123,166 Lubbock, TX...Abilene, TX...Midland, TX...Odessa, TX...San Angelo, TX...
Probabilistic Tornado Graphic
20181012 1200 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
2 % 21,428 385,069 Midland, TX...Odessa, TX...Big Spring, TX...West Odessa, TX...Pecos, TX...
Probabilistic Damaging Wind Graphic
20181012 1200 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 61,612 673,349 Midland, TX...Odessa, TX...San Angelo, TX...Del Rio, TX...Eagle Pass, TX...
Probabilistic Large Hail Graphic
20181012 1200 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 97,103 2,119,601 Lubbock, TX...Abilene, TX...Midland, TX...Odessa, TX...San Angelo, TX...
   SPC AC 120542

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1242 AM CDT Fri Oct 12 2018

   Valid 121200Z - 131200Z


   A few marginally severe thunderstorms may develop across parts of
   west Texas and far southeastern New Mexico this afternoon and

   Presence of several disturbances (including a few shortwave troughs
   and two tropical systems) will contribute to a fairly active upper
   pattern today. Tropical cyclone Michael is expected to accelerate
   quickly northeastward into the northern Atlantic, likely influenced
   by a strong shortwave trough expected to move across the northern
   and central Plains and much of the OH Valley. Upper low initially
   off the central/southern CA coast will gradually move southeastward
   towards far southern CA/northern Baja Peninsula. Movement of this
   upper low will likely effect tropical cyclone Sergio, which is
   expected to move quickly northeastward across the central Baja
   Peninsula and northern Mexico before moving into the southern High
   Plains as a remnant low late in the period.

   ...Southeast NM and Far West TX into TX Rolling Plains...
   Moisture advection is anticipated across the region ahead of the
   approaching tropical system, with dewpoints expected to reach as
   high as the mid 60s as far west as the Pecos River. Large-scale
   forcing for ascent will likely be negligible throughout much of the
   afternoon but convergence along a weak surface trough could
   contribute to isolated thunderstorm development. The air mass is
   only expected to be moderately unstable (largely a result of poor
   mid-level lapse rates) but the strengthening mid-level flow ahead of
   Sergio will result in bulk shear profiles supportive of rotating
   updrafts. Isolated hail and strong wind gusts are possible with any
   more persistent development.

   Thunderstorm coverage is expected to increase after 00Z Saturday as
   forcing for ascent increases ahead of Sergio. This ascent will be
   augmented by strengthening low-level southeasterly flow. Surface low
   associated with this system is expected to move across far west TX
   from 06Z to 12Z with much of the thunderstorm activity anticipated
   north of this track. As a result, these thunderstorms will
   predominately be elevated. The air mass will remain only moderately
   unstable but vertical shear is supportive of organized storms and a
   few instances of marginally severe hail are possible. Additionally,
   troughing extending east of the low may provide a corridor where a
   higher probability of surface-based storms exists. In this corridor,
   increased updraft strength as well as better low-level moisture and
   southeasterly surface winds may result in an environment supportive
   of tornadoes. Timing is sub-optimal and the storm mode appears more
   linear but the threat appears high enough to merit a small 2%
   tornado area. Strong wind gusts could also be realized in this same

   ..Mosier/Gleason.. 10/12/2018