The Storm Prediction Center convective weather outlook is part of the National Weather Service (NWS) and the National Center for Environmental Prediction (NCEP). Their mission is to provide accurate forecasts and monitor the timing of thunderstorms and severe storms in the United States. The SPC provides convective outlooks on Day 1, Day 2, and Day 3 that reflect the overall level of severe weather hazard outlooks through a list of forecast statistics. This data identifies areas at risk of mild thunderstorms and severe thunderstorms. For more information on how to read this map, please see the bottom of this page.
Convective Outlook Day 1
SPC Day 1 Outlook Discussion
ACUS01 KWNS 130026 SWODY1 SPC AC 130025 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0625 PM CST Fri Dec 12 2025 Valid 130100Z - 131200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible in the vicinity of the Lower Texas Coast later tonight. ...01z Update... Low-amplitude short-wave trough is embedded within the southern stream over deep South TX. This feature is shearing east toward the northwestern Gulf basin where it is expected to encourage isolated thunderstorm development, primarily off the south TX Coast later tonight. 00z sounding from BRO was notably capped with strong inhibition around 2km. Latest model guidance suggests inhibition will gradually weaken which may allow isolated offshore convection to gradually approach the coast later tonight. Even so, this activity should remain weak with the greater concentration holding offshore. ..Darrow.. 12/13/2025 $$ |
Convective Outlook Day 2
SPC Day 2 Outlook Discussion
ACUS02 KWNS 121711 SWODY2 SPC AC 121709 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1109 AM CST Fri Dec 12 2025 Valid 131200Z - 141200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated weak thunderstorm activity is possible across portions of the Texas and Louisiana coasts, as well as South Florida and the Keys Saturday afternoon into Saturday night. ...Gulf Coast... An upper trough will deepen over the eastern half of the CONUS on Saturday, though stronger west/northwesterly flow will be displaced well to the north of the region. At the surface, strong high pressure will build over the Plains into the Midwest, shunting a weak cold front south across the western and central Gulf Coast vicinity during the overnight hours. Modest moisture will be in place along the TX coast into the central Gulf coast vicinity, with richer tropical moisture across South FL and the Keys. This will allow for modest destabilization ahead of the boundary. Weak forcing for ascent, warm midlevel temperatures, and weak instability will preclude strong updrafts. Nevertheless, isolated thunderstorm activity will be possible near the TX coast into southwest LA, as well as South FL and the Keys. ..Leitman.. 12/12/2025 $$ |
Convective Outlook Day 3
SPC Day 3 Outlook Discussion
ACUS03 KWNS 121845 SWODY3 SPC AC 121844 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1244 PM CST Fri Dec 12 2025 Valid 141200Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few storms are possible across South Florida and the Florida Keys on Sunday. ...Synopsis... An upper trough will move across the eastern CONUS and offshore the Atlantic coast Sunday night/early Monday. At the surface, strong high pressure will continue to build south and east from the Mid-MO Valley to the TN Valley. As this occurs, a weak cold front will move southeast across GA/SC and FL. Richer boundary layer moisture will remain confined to South FL and the Keys where showers and isolated thunderstorms may be ongoing Sunday morning. This activity may persist into the afternoon while shifting southeast with time. Weak instability and modest vertical shear will preclude severe thunderstorm potential. ..Leitman.. 12/12/2025 $$ |
Convective Outlook Day 4-8
SPC Day 4-8 Outlook Discussion
ACUS48 KWNS 120921 SWOD48 SPC AC 120919 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CST Fri Dec 12 2025 Valid 151200Z - 201200Z ...DISCUSSION... Strong high pressure will dominate the eastern CONUS on Monday with offshore flow across then entire Gulf Coast and East Coast. This dry, continental polar airmass across the eastern CONUS will result in no thunderstorms east of the Rockies on Monday and Tuesday. Some thunderstorms are possible along the coastal Pacific Northwest where some weak instability may be present. By the middle of next week, moisture return should resume across Texas. This may result in some thunderstorm activity by early Wednesday in the east Texas vicinity. Beyond Wednesday, model uncertainty increases substantially. However, severe potential will still remain too low as even the most favorable mid-long range guidance indicates minimal instability and low severe weather threat. ..Bentley.. 12/12/2025
Convective Weather Outlook Legend Data
- TSTMÂ (light green) – General or non-severe thunderstorms – Delineates, to the right of a line, where a 10% or greater probability of thunderstorms is forecast during the valid period.
- 1-MRGL (dark green) – Marginal risk – An area of severe storms of either limited organization and longevity, or very low coverage and marginal intensity.
- 2-SLGT (yellow) – Slight risk – An area of organized severe storms, which is not widespread in coverage with varying levels of intensity.
- 3-ENHÂ (orange) – Enhanced risk – An area of greater (relative to Slight risk) severe storm coverage with varying levels of intensity.
- 4-MDT (red) – Moderate risk – An area where widespread severe weather with several tornadoes and/or numerous severe thunderstorms is likely, some of which should be intense. This risk is usually reserved for days with several supercells producing intense tornadoes and/or very large hail. Or an intense squall line with widespread damaging winds.
- 5-HIGH (magenta) – High risk – An area where a severe weather outbreak is expected from either numerous intense and long-tracked tornadoes. Also, a long-lived derecho-producing thunderstorm complex that produces hurricane-force wind gusts and widespread damage. This risk is reserved for when high confidence exists in widespread coverage of severe weather with embedded instances of extreme severe. (i.e., violent tornadoes or very damaging convective wind events).
This data is courtesy from the Storm Prediction Center