A very strong upper-level low pressure system is currently centered to the West of Las Vegas, as shown on the water vapor satellite image above. This system caused flash flooding and spotty severe weather over southern California as well as portions of Nevada and Arizona yesterday and overnight.
Several disturbances will continue to flow around the base of the system today, moving out into the adjacent High Plains to the East of the Rockies (as shown by the purple arrows). These disturbances will interact with increasing low-level moisture and instability to produce a threat of severe weather.
The greatest chance of severe weather this afternoon and evening is expected to extend from southwest Texas, Northward along the New Mexico and Texas border, into southwestern Kansas, as shown by the yellow shaded area on the image below:
Thunderstorms that form in this region later today and into this evening and early tonight will be capable of producing large hail, damaging winds and even a few tornadoes. The greatest risk for a tornado will be located within the brown shaded area on the following image:
As we expected yesterday, thunderstorm activity formed overnight and early this morning along the Kansas/Oklahoma border, Eastward into southern Missouri and northern Arkansas. This activity is currently moving Southeastward, as shown by the composite radar image shown below:
Some of this activity may strengthen during the midday and early afternoon hours as it approaches a moist, unstable airmass over southeastern Oklahoma and southern Arkansas. Strong wind gusts would be the primary threat with this activity.
The main threat of severe weather today will develop later this afternoon and into this evening back to the West along a dryline near the Texas/New Mexico border, on Northward into the Oklahoma panhandle and southwest Kansas. This threat will mainly take place after 2-3pm today, with all modes of severe weather (large hail, damaging winds and a few tornadoes) possible in this region.
If you live in the severe weather threat areas for today, please remain alert and listen for later forecasts, watches and warnings. Take a few moments early in the day to identify your best sheltering option and be prepared to move there quickly if threatening weather is observed or a warning is issued.
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