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Turning Stormy in the Northwest

An active fall storm pattern developing in the Pacific Northwest this week will bring areas of heavy rain and high elevation snow. Northern California will benefit from rainfall this week that will aid firefighters given the recent large wildfires. Read More >

Partly cloudy. Increasing cloudiness late across Central Texas. With increasing humidity, low tonight will be in the 50s. Winds will be southeast at 5 to 10 mph.
We will have increasing cloudiness and warm Thursday. Highs in the 80s. Southeast winds 5 to 10 mph.
Southerly winds will bring increasing Gulf moisture to the region Thursday through Friday. Low chances of showers and thunderstorms will return Thursday night through Friday evening with the approach of an upper level disturbance. Lows Thursday night will be in the mid 50s to lower 60s and with increasing humidity lows Friday night will be in the 60s area wide. Highs will be in the upper 70s to lower 80s Friday.
There will be a chance of showers and thunderstorms during the day Saturday. The better threat for more organized thunderstorms will be Saturday evening through Sunday morning ahead of a cold front. Some of these storms may become severe, producing damaging winds and large hail. Locally heavy rain that could result in flooding and cloud to ground lightning will also be possible. Expect gusty northerly winds behind the front that will sweep through the Bowie and Breckenridge areas before midnight and through the Palestine and Cameron areas by late Sunday morning.

 
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Automatically generated image showing areas of energy helicity index.

 

Thumbnail of an automatically generated image showing areas of energy helicity index. Thumbnail of an automatically generated image showing areas of energy helicity index. Thumbnail of an automatically generated image showing areas of energy helicity index.
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EHI 

The Energy Helicity Index (EHI) is a number which represents the combination of instability and storm relative helicity.  Our calculation uses mixed layer CAPE (surface to 3000ft average parcel) and 0-3 km storm relative helicity.  Values greater than 2 or 3 have been correlated to cyclonic supercells with increased tornadic potential.  Negative values are indicative of an environment favorable for anti-cyclonic (left moving) supercells, but tornadoes associated with anti-cyclonic supercells are extremely rare.

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