Very Warm... & Thunderstorms

High temperatures today were able to reach the 70s throughout most of the state, although some cloud cover kept the eastern portions of the state slightly cooler. And a weak boundary also kept the warm air from reaching too far east. The mid to upper 70s were prominent in the western third of the state, where record highs were being challenged. One confirmed record high came from Estherville, where the high reached 76 degrees, breaking the old record of 75. Other records may end up being tied, they were at least within a few degrees.

The warm air will continue tomorrow, in fact with near record temperatures once again occurring across a majority of the state this time around. We'll start out tonight with lows in the lower to mid 50s, as increasing moisture may also lead to some fog development. Tomorrows highs will be in the mid 70s throughout the entire state, but expect some localized areas to reach the upper 70s. These highs will accompany dewpoint increases well into the 50s as southerly winds begin to push moisture up from the south. Monday night lows will be hampered in the northwest as a weak cold front slides in and stalls out overnight. Mid to upper 40s over northwest Iowa, while lower to mid 50s will cover the rest of the state. Tuesday highs won't be quite as warm, but still well above average in the lower to mid 70s across Iowa. The main reason for the lower temperatures on Tuesday may be due to some increase in clouds, and gusty southerly winds of 10-25 mph. Tuesday night will begin to bring in some precip chances for mainly northwest Iowa, however, these precip chances may be taken out depending on timing issues with the storm system entering the state. Tuesday night lows will range from the lower 50s in the east to the upper 50s in the west under cloud cover.

Beyond Tuesday night the forecast really gets interesting with talk of the first big Fall severe weather event for the state of Iowa. A strong low pressure system will develop off the Rockies and move into the plains with an associated strong Canadian trough. The combination of strong southerly winds, bringing in heat and moisture, and this strong frontal system and associated low will bring in likely chances of thunderstorms. Given the good instability and shear also present, the severe weather threat is also present. The most recent discussion from Des Moines NWS touches on the possibility of all modes of severe weather, including tornadoes. This event may likely end up being what is termed a cold core low severe weather setup, where low topped supercells that may have fast movement are able to rotate rapidly and bring in the chances of tornadoes. This risk has been on the rise as weather models are coming into an agreement with a strong low tracking near or through the state of Iowa. More details on the severe weather threat will be discussed in updates on Monday and Tuesday as the event nears.

Beyond this severe weather event, as the low wraps up to the east of the state we will see a strong influx of cold air. With precipitation lingering, many of the NWS offices have decided to include the risk of a mix of rain/snow chances for Thursday night into Friday morning. So the potential for severe weather, followed by snow showers within 24 hours, is definitely there for the state. The risk of snow will also be discussed in midweek updates, most likely after the severe weather risk is detailed.