A strong storm system will bring very strong winds, strong storms and light snow to the area Wednesday. The Iowa Storm Center wind and severe models are included so read on for the details…
A strong pacific storm will impact Iowa Wednesday starting with strong southerly winds in the afternoon. The wind gusts will peak later Wednesday evening as the low level jet intensifies and this will lead to much of the state with level 5 and level 6 wind values on my scale. This may result in power outages, especially those from southwest Iowa into central and northeast Iowa where my wind gust intensity model is showing a 6 for these areas. High profile vehicle roll-over will be likely in this zone. For this reason, I have replaced the High Wind Watch with a High Wind Warning in effect Wednesday afternoon through Wednesday evening for most of the state excluding a small area of southeast Iowa where I have issued a Wind Advisory for wind gusts that won’t be as intense. High temperatures on Wednesday expected to spike into the 50s, 60s and even lower 70s from central to southern Iowa.
While these strong winds are in progress this will set the stage for severe weather dynamics across western Iowa and into northern Iowa just southeast of the upper level low. Instability with shear of 70-90 kt will warrant a cold core setup capable of mainly damaging winds. If dynamics can become more defined, a small tornado risk could exist along the frontal zone from northwest into north central Iowa. Keep in mind these individual cells that do develop Wednesday afternoon will be moving very quickly to the northeast. The only thing that will change this from happening is if the cap does not break. That being said, further updates may follow regarding the severe weather evolution on Wednesday. The backside of the storm system will hit later Wednesday evening with colder temperatures and maybe even some light snow across northwest Iowa before the system pulls off to the northeast.
Iowa Storm Center Severe Risk –
Iowa Storm Center Wind Gust Intensity Scale –
Level 6. Damage may occur to buildings and trees. Power outages possible. High Profile Vehicle Roll-Over Likely. Do NOT recommend traveling in this zone.
Level 5. Some trees are broken, building damage possible. High Profile Vehicle Roll-Over Likely. HIGH WIND WARNING CRITERIA
Level 4. Slight damage may occur to trees/buildings. High Profile Vehicle Roll-Over Possible.
Level 3. Small branches may break, walking is difficult.
Level 2. Large trees sway, becoming difficult to walk. WIND ADVISORY CRITERIA
Level 1. Small trees sway, breezy