More Weekend Storms

Well if two straight days of thunderstorms isn't enough for portions of the state, there will only be a one day break before another round of severe storms hits Iowa. Last night saw another round of severe weather, mainly over the southern half of the state, and the most significant once again occurring over the southwest quarter where more tornadoes touched down. Early afternoon storms over portions of NE/SD and northwest Iowa brought the first warnings of the day, mainly for large hail and damaging winds; as well as flash flooding. These storms were just one ingredient that likely hampered additional development along the warm front in northern Iowa during the later evening hours. Storms that initially fired in Kansas worked northeastward and entered extreme southwest Iowa by the late evening hours with the threat of large hail, winds, and tornadoes. Just after 7 PM a tornado touched down just across the Iowa border to the east of Nebraska City, KS. As storms continued to move east/northeastward additional tornadoes were reported near Randolph, Cumberland, Creston, Monroe, and Kellogg. Other than tornadoes a few tornado reports near Ames & Boone (Nickel-Sized Hail), and several damaging winds with the relatively weaker thunderstorms. The damaging winds were likely a combination of not only thunderstorm strength, but the environmental wind fields were also very strong, leading to these high winds. Damage was even reported behind these thunderstorms with the strong environmental wind fields, measured gusts from Spencer were upwards of 58 mph; and a gust measured at my home near Terril reached 68 mph.

Temperatures today range from the mid 60s in northwest Iowa under mostly cloudy skies, to the mid 80s in the southeast under clear skies. Winds are still strong today from the southwest, 15-30 mph on average with higher gusts likely throughout the state. Highs today should be just a degree or two higher than current temperatures indicate. Lows overnight should range from the upper 50s to upper 60s from northwest to southeast; winds should begin to subside and switch to more of a southerly direction under partly cloudy skies. Weekend temperatures will have highs in the upper 70s to lower 90s on Saturday from northwest to south; highs on Sunday from northwest to southeast will range from the mid 70s to upper 80s. Lows overnight in the mid 50s to upper 60s for both Saturday and Sunday night. Thunderstorms likely during the day and night on Saturday, with additional thunderstorms throughout the day on Sunday and Sunday night. Severe weather chances for both days, the best chance on Saturday which is described in more detail below.

Saturday, June 7 Severe Weather Possibilities
A cold front will enter the state during the morning or early afternoon hours from the north/northwest and continue southward into the state. This front throughout the day will decelerate with time, potentially even becoming stationary across the state in the afternoon. Thunderstorms will more likely develop along this front in the afternoon, with strong instability in place with very warm temperatures and dewpoints pushing the 70-mark. The threat of these thunderstorms will likely pose for all threats of severe weather, however, the best chance for tornadoes does look to exist over the western half of the state during the late afternoon and evening hours. Large hail and damaging winds do look to be the greater threat, but discrete storms may pose the tornadic threat as mentioned. Timing will see thunderstorms initially develop over MN/WI and the northeastern quarter of the state during the mid-afternoon. Late-afternoon and evening expansion of thunderstorms over eastern Nebraska and western Iowa will then occur an hour or two later, with a potentially higher severe weather threat.

The SPC has the area under a slight risk, with probabilities of 30% and hatched indicating an enhanced severe threat over nearly the entire state. Later outlooks may upgrade this area to a moderate risk if conditions do warrant and updates to the blog will reflect that. Although the chase yesterday busted, depending on how the morning satellite and forecasts look, it may be worth another chase in Iowa tomorrow!