Humidity rises as low pressure nears the Stateline


Sunday’s high temperature of 91 degrees marked the fourth day in a row where the high temperature reached 90 degrees or higher. While the streak may end Monday, the humidity will certainly be on the rise.

Dew point temperatures these last few days have been tolerable, remaining in the 50s. This meant that the ‘heat index’ temperature actually felt like, if not a little cooler, the actual air temperature. Now the 94 degree high temperature we tied with for a record Saturday was hot – no doubt about that – but it could have been far more humid.

Unfortunately the rise in humidity will be felt throughout the next several days as southerly winds draw a bit of gulf moisture northward. Those southerly winds are in response to an area of low pressure cut-off from the main flow of the jet stream.

We’ve really had a more summer-like pattern for the start of June as the jet stream has buckled more to the north, leaving more of the active weather near the U.S./Canadian border. The low pressure system cut-off from the jet stream currently sits in the central Plains and has brought widespread shower and thunderstorm activity across the parts of the lower 48. Most of the heavier rain has been down near the Gulf, with slow moving showers producing a few flash flood warnings across Arkansas and Oklahoma, as well as shower/storm activity along the front range of the Rockies.

An isolated shower or two remains possible for us here in the Stateline Sunday evening but most locations will remain dry. The increase in the cumulus clouds during the afternoon was a sign that moisture was beginning to overspread much of the region, but it was still too dry to really get some much needed rain. And while the rain chances go up this week the rain activity remains more isolated to scattered, and not widespread that most areas in northern Illinois and southern Wisconsin so desperately need.

Our first chance for shower activity arrives Monday afternoon with the heating of the day. The rain will not be evenly distributed, but where the rain does come down there could be a few lucky ones that receive over an inch or so – given how much moisture will be present in the atmosphere. We may see the rain activity increase slightly for Tuesday and Wednesday as the upper level low nears the Stateline. By Thursday it’ll be shifting more to the east which means our rain chance goes back down to more isolated during the afternoon and early evening. Unfortunately the incoming rain chance won’t be too widespread, meaning there could be some who don’t get much rain – if any at all – this week. Often times in drought situations it’s really hard to get the needed rain. And that could be something we’re in for with this more active pattern this week.

Beyond next week the overall pattern does look to remain hot and dry.

Copyright 2021 Nexstar Media Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.