A Big Cooldown Arrives to End May

Linda Lam
Published: May 31,2015




 
A big cooldown has overtaken parts of the Midwest and Plains this weekend. The cooler air mass is also spreading towards the Northeast for the start of the new week.
This will be a huge change from this past week. Some areas will see temperatures as much as 20 degrees cooler, as highs slide from the 80s into the 50s and 60s.

Temperatures will be closer to what you expect in mid-to-late April than heading into June.
The cooler air is courtesy of a late spring cold front pushing south and east into early week. However, the cold front will not make it into the South, leaving the warm, humid and stormy conditions in the region.
(MAPS: Current Conditions)
Let's examine the chilly details for the Midwest and Northeast below.

Cooler Midwest and Plains

Noticeably cooler temperatures were felt in the Upper Midwest and Plains Saturday with highs generally in the 50s and 60s in the Dakotas, Minnesota and Wisconsin.
On Sunday morning locations as far south as northern Illinois, including Chicago, woke up to wind chills in the 30s. The actual air temperature dipped to the freezing mark (32 degrees) in a few spots across northern Wisconsin and northern Minnesota.
(FORECAST: Minneapolis | St. Louis | Detroit)

Forecast Highs

On Sunday, the entire Midwest will see temperatures lower than you would expect at this time of year, with highs generally in the 50s and 60s. It will be a little warmer in the central Plains where high temperatures will reach the 60s and 70s.
The cooler highs will make it feel more like mid-to-late April for many cities including Chicago where highs may only reach the 50s on Sunday, compliments of winds off Lake Michigan. Oklahoma City will see highs only in the 70s (average high for the end of May is in the mid-80s).
Overnight lows will be chilly and are expected to dip into the 30s and 40s in the northern Plains, Upper Midwest and Great Lakes through Tuesday morning with 50s through much of the Plains.
(MAPS: 10-day Forecast)

A slow warm-up back to more typical early June levels is anticipated midweek as an upper-level ridge begins to build into the Midwest.

Northeast Temperature Drop

Cool temperatures will spread east into western New York and northern New England on Sunday. Many locations will be more than 20 degrees colder than late this past week.
High temperatures will be 10 to 20 degrees below average instead of 10 to 20 degrees above average like we saw much of this past week.

Forecast Highs

Hopefully, you haven't put the spring jacket away yet as Monday and Tuesday highs will mainly be in the 60s and 70s across the region with even a few 50s in spots. Lows will typically drop into the 40s and 50s.
(MAPS: Weekly Planner)
Highs in New York City have been in the 80s for the past week, but to start the work week temperatures may only climb into the 60s, which is closer to the low temperatures from this past Wednesday and Thursday (a low of 70 was recorded both days).
Boston will see temperatures plummet from Saturday's upper 80s to highs only in the 50s Monday and Tuesday -- which is a change of more than 30 degrees.
Low temperatures will return to near to slightly below average. A few record warm low temperatures were set this past week including in Syracuse, New York which set a record of 71 degrees on Wednesday, which is warmer than the expected high on Sunday, Monday and Tuesday.
(FORECAST: Philadelphia | Buffalo | Pittsburgh)
Along with the cooler temperatures, humidity levels will drop too. Dew points will fall back into the comfortable range with readings in the 40s and 50s by midweek.
The cold front will also increase the risk of thunderstorms and a few storms could become severe, especially in those areas where the cold front passes later in the afternoon and early evening. The best chance for strong to severe thunderstorms will be in the Mid-Atlantic on Sunday afternoon.
(MORE: Severe Forecast)
The chance for much-needed rain will continue in the Northeast early this week, as the cold front will linger in the region, which will also help to keep the temperatures down.
Temperatures will remain cool into midweek before another round of warm conditions develop late week, as a southerly flow returns to the Northeast.
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