Sun’s back in what’s been the cloudiest February open in 9 years–precip’s been running more than 4 times normal the past 2 weeks

Filtered sunshine’s return Wednesday is likely to be especially welcome given the month’s paltry sunshine tally to date. Just 25% of the area’s possible sun has been measured in that period, a fraction of the 47% considered normal in February. That makes February 2013 the cloudiest of the 9 years since 2004. The month’s sun amounted to just 22% normal then.


The 4.19” water-equivalent precipitation on the books makes it the wettest Jan 27 to Feb 12 period in 143 years of Chicago weather records


It’s little wonder precipitation has been elevated this month even as the city’s allocation of sun has taken a hit. Measurable precipitation has fallen 11 of the past 17 days and the 4.19” on the books since January 27 demolishes the record for the period. There’s never been a January 27 to February 12 period that’s been any wetter here.


Pattern changes can be dramatic—but also quite temporary.  It was January 27 the first in a series of wet weather systems rode into the Midwest from the Pacific.  Their impact on Chicago’s weather has been stunning. Just 0.90” of precip is considered “normal” from Jan 27 to Feb 12, a value which has been obliterated by the actual 4.19” tally.


Late season arctic air’s return and indications of winds the length of Lake Michigan into Chicago increase lake-enhanced snow shower chances Friday and Saturday


The manner in which late season arctic returns to the Midwest is to be quite noticeable late this week into the coming weekend. There are computer model suggestions that winds several thousand feet above ground-level may blow south into Chicago, traveling the length of Lake Michigan before reaching the city.  It’s a set up which boosts chances that areas adjacent to Lake Michigan may be visited by lake-enhanced snow showers, born as cold air makes contact with warmer lake water—so-called “lake-effect” snow.


Two storm systems may sweep Chicago next week; a wintry Monday mix of precip changing to snow predicted with the first


Forecasters will be monitoring two potential storm systems next week—the first due into the area later Monday and Tuesday.


Second system looking more formidable; its Thursday/Friday snow threat here makes it a system worth monitoring—but not yet carved in stone


The potentially more formidable of next week’s two systems could be the second one. Model projections develop a winter storm which tracks south to Texas then could hook north/northeast into the Midwest with snow in tow late in the week.


At the time ranges in which both of next week’s systems are to occur, neither is a slam-dunk just yet.  But the fact all major global models carry the new system lends credence to the notion they may actually occur. Details on their precise track and the exact amount of precipitation they may produce are unreliable at this range in time. But computer modeling of the weather has improved to such a great extent that systems like these shouldn’t be dismissed.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s