Convective Outlook
— Day 1
No Thunderstorms Forecast
Summary
Thunderstorm probabilities appear less than 10 percent across the U.S. today through tonight.
Discussion
Models indicate that blocking within the large-scale pattern will remain prominent through this period. This includes one notable mid-level high, which may build further while slowly beginning to shift inland of the southern California coast, into the Southwest. As this occurs, large-scale ridging likely will be maintained across the offshore mid-latitude Pacific through the Rockies, with at least some expansion eastward across the Great Plains.
It appears that another mid-level high may attempt to form downstream, within initially amplified large-scale ridging across the western mid-latitude Atlantic, as a couple of significant short wave perturbations emerge from lingering larger-scale troughing initially across the Mississippi Valley through Atlantic Seaboard. Both of the waves are forecast to rapidly accelerate within strong southwesterly flow into the northern mid-latitude Atlantic.
As this occurs, a broad, deep and occluding surface cyclone is forecast to migrate northeast of the eastern Canadian provinces, with the trailing cold front advancing away from much of the Atlantic Seaboard, while slowing/stalling across the Bahamas into Caribbean. The center of cold surface ridging likely will shift from near the northwestern Gulf coast into the Mid Atlantic vicinity today through tonight, but models indicate that surface ridging will be maintained to the southwest, across much of the Great Basin.
In association with this regime, dry and/or stable conditions are likely to prevail across much of the U.S., with negligible risk for thunderstorm activity today through tonight.
000 ACUS01 KWNS 170444 SWODY1 SPC AC 170443 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1143 PM CDT Mon Mar 16 2026 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm probabilities appear less than 10 percent across the U.S. today through tonight. ...Discussion... Models indicate that blocking within the large-scale pattern will remain prominent through this period. This includes one notable mid-level high, which may build further while slowly beginning to shift inland of the southern California coast, into the Southwest. As this occurs, large-scale ridging likely will be maintained across the offshore mid-latitude Pacific through the Rockies, with at least some expansion eastward across the Great Plains. It appears that another mid-level high may attempt to form downstream, within initially amplified large-scale ridging across the western mid-latitude Atlantic, as a couple of significant short wave perturbations emerge from lingering larger-scale troughing initially across the Mississippi Valley through Atlantic Seaboard. Both of the waves are forecast to rapidly accelerate within strong southwesterly flow into the northern mid-latitude Atlantic. As this occurs, a broad, deep and occluding surface cyclone is forecast to migrate northeast of the eastern Canadian provinces, with the trailing cold front advancing away from much of the Atlantic Seaboard, while slowing/stalling across the Bahamas into Caribbean. The center of cold surface ridging likely will shift from near the northwestern Gulf coast into the Mid Atlantic vicinity today through tonight, but models indicate that surface ridging will be maintained to the southwest, across much of the Great Basin. In association with this regime, dry and/or stable conditions are likely to prevail across much of the U.S., with negligible risk for thunderstorm activity today through tonight. ..Kerr.. 03/17/2026 $$