Atmospheric River to Begin to Impact the Northwest U.S.; Gusty Winds in the Northeast U.S.

A strong atmospheric river moving into northern California later Tuesday will bring a threat for moderate to heavy rainfall and flooding, gusty to high winds, and mountain snows for parts of the Northwest U.S. through at least Wednesday. Gusty winds and isolated rain and snow showers will continue in the Northeast U.S. Tuesday behind a cold front. Read More >

Graphical HWO - Thunderstorm Threat

This graphic reflects both the severity of any thunderstorm activity that may develop, as well as the potential coverage of severe thunderstorms.

For example, an area under the "Strong to Severe" category, at worst, will see storms that have severe-criteria damaging winds or large hail. However, only a few of the storms that will develop are expected to meet these criteria.

Click the graphic to return to the graphical HWO page.

Categories

No Storms	Thunderstorms are NOT EXPECTED during the period.
General	Strong or severe thunderstorms are not anticipated. The main hazard with any storms would be cloud to ground lightning and brief gusty winds (30 mph or less).
Strong	Some strong thunderstorms are possible, with the main threats being frequent cloud-to-ground lightning, wind gusts to 50 mph, and hail to 1/2" in diameter.
Strong to Severe	The majority of storm activity is expected to remain below severe criteria. However, a few severe storms are possible, with the main threats being wind gusts to 60 mph and hail up to 1" in diameter.
Severe	There is an increasing probability of severe thunderstorms. The primary threats would be winds greater than 60 mph and hail up to 2" in diameter. Isolated, weak tornadoes are possible.
Widespread Severe	The occurrence of significant severe weather is likely. The main threats would be wind gusts in excess of 80 mph, very large hail (greater than 2" in diameter), along with an increasing threat for tornadoes. An isolated strong or violent tornado (F2 intensity or greater) is also possible.

Atmospheric River to Begin to Impact the Northwest U.S.; Gusty Winds in the Northeast U.S.

Thunderstorm Threats NWS Huntsville, AL