Monday morning temperatures began their jump right above the freezing mark. By the time Tuesday afternoon rolls around, we will have lived through a rise of more than fifty degrees!

Thankfully for any of our farmers in the fields, the warmth will not come with showers and thunderstorms. That’s thanks to low levels of humidity. However, with time, showers and thunderstorms will become more widespread across the Upper Midwest.

On Wednesday, a cool front will stall across Central Illinois and Indiana, moving the “storm zone” south of our area. This is not a good set up for agriculture efforts downstate. But this stalled-out front will eventually move back to the north as a warm front…sparking a few thunderstorms in Northern Illinois and Southern Wisconsin Friday and Saturday.

Then, we’ll be watching the progress of a low pressure system ejecting out of the Rockies. The Storm Prediction Center already has an area highlighted for Saturday in the Central Plains (Click here to read the technical discussion.) .

Posted under cold blast, heat wave, severe weather

Frost Advisory Map

As mentioned in this blog post yesterday, freezing temperatures are not out of the ordinary in northern Illinois and southern Wisconsin this time of year.  Overnight and into early Monday morning, temperatures are expected to fall into the lower 30s.  Because of that, a Frost Advisory has been issued for the entire 13 WREX viewing area.

A Frost Advisory is in effect from 1:00am through 7:00am for Winnebago, Boone, DeKalb, Lee, McHenry & Ogle County.  Green, Rock & Walworth County in Wisconsin are also under a Frost Advisory for the same time period.  Chilly temperatures are expected area-wide so all counties in our area will have the threat for patchy frost.

(3:30pm Update) The counties of Carroll, Jo Daviess, Stephenson & Whiteside have now been added to the Frost Advisory from 2:00am through 7:00am Monday.

Even though we are not expecting a hard freeze, make sure you plan accordingly and cover any tender vegetation which may be susceptible to frost.

-Joe

Posted under cold blast, frost, weather

During the late winter and early spring, the reservoir of cold water known as the Great Lakes can cool surrounding areas considerably! Today, we shot into the 70s while much the big cities and suburbs to our east saw 60s. A northeasterly wind in March and April can bring our temperatures down by as much as twenty degrees. However, with water temperatures rising into the 50s now, the strength of that cooling will become confined to areas closer to the lakeshore. Still, as we know, that “cooler by the lake” phrase will be used quite a bit by our Meteorologist friends in Milwaukee and Chicago. However, in a few weeks, it will be pretty hard to get that cooling this far inland.

More importantly, will be the cold bursts of air from Canada…and there’s one coming for the weekend. Models are consistent in bringing a cold front through the area Saturday. Depending on the strength of the airmass behind it, temperatures may only top out in the lower 50s by Sunday…a far cry from this past weekend.

However, don’t fret. This is way out on Day-6 of our 7 Day Outlook. We could see this cold air modify a bit and even delay, which could cause us to bump up those forecast highs.

Posted under cold blast, weather geek

We are closing in on the last week of March and have a very good shot at ending the month with only one day at or above the average high temperature. That is as far away from last year’s March as we could get. Last year we saw an impressive and highly unusually warm March with temperatures soaring above 80 degrees for nearly a week straight. Those well above average temperatures were a gift at the time, but they also helped spark our extreme drought that endured the rest of the year. This year’s temps are down, but our precip is steadily gaining ground and not going into the negative. I don’t know about you, but I can handle a few more weeks if it lessens our chances for another extreme drought this summer. -Greg

Posted under cold blast, drought, statistics, winter weather

Looking at high temperatures for each of the 20 days of March reveals a stunning feat! Every day has seen a high temperature below average, except for one – on March 10th we touched the normal high.

Looking ahead through the end of the month, it is likely we will continue with the below-average stretch. Our average high temperatures will soon go into the 50s and the warmest temperature we have forecast for the next week is the upper 30s. 50s seem highly unlikely through the first part of April.

One of the biggest factors in the cold air is the negative phase of the “North Atlantic Oscillation.” The NAO, for short, is the jet stream’s orientation in the North Atlantic. We’ve learned over the past decade that the location of the jet determines how the storm systems and airmasses move over our continent. This allows the coldest air of the hemisphere to be shunted southward over the central continent. Unfortunately, the NAO is forecast to remain negative for the next week or two — however, it will weaken some.

Welcome to spring! -Eric

Posted under climate/climate change, cold blast

A strong, late-Winter cold front passed through northern Illinois and southern Wisconsin on Monday. The result was minor snow accumulations followed by plummeting temperatures and a gusty wind.  Sustained wind speeds will range from 20 to 30mph out of the west-northwest Monday night.  Wind gusts may top 40mph!  Wind chills will slide toward zero and may dip below zero early Tuesday morning. The brisk wind will continue through the day Tuesday, with gusts around 30mph at times. A stray flurry or two is possible, but no accumulation is expected. Otherwise, it will be partly cloudy. Temperatures will only rebound into the upper 20s to near 30.  With temperatures likely falling in the single digits Tuesday night and Wednesday morning, wind chills will once again fall below zero.

Interesting of note, Wednesday March 20 is the Spring Equinox.  Wednesday’s record cold high temperature in Rockford is 22 degrees, which occurred in 1965. Our forecast high is currently 24 degrees!  Not the greatest way to usher in Spring!  To add insult to injury, March 20th’s normal high temperature is 49 degrees.  Just last year in 2012, we hit a record 83 degrees on that date!  I don’t know about you, but I’m definitely ready for things to warm up!

-Joe

Posted under 13 Climate Authority, cold blast, FutureTrack, record weather, statistics, weather, Wind

St. Patrick’s Day 2013: Chilly by Comparison

A normal St. Patrick’s Day across the Stateline would bring high temperatures in the upper 40s.  In fact, this is the time of year where even 50 degree temperatures and light jackets are expected.  That will not be the case this year as our highs will struggle to climb to 35 degrees!  Last year was not normal either.  Many of us, myself included, felt like we found the pot of gold!  On March 17, 2012 Rockford recorded the warmest temperature ever for the Irish holiday at 82 degrees!  Many were enjoying the sun and warmth in summer attire!

Will our March 2013 cool spell come to an end? Signs point to 40 degrees by next weekend, which is still about 10 degrees cooler than where we should be.  The longer-range forecast models keep us below average for most of the rest of the month.  No Irish luck this year, unfortunately.

-Joe

Posted under 13 Climate Authority, cold blast, record weather, statistics, weather

Last year on this date, the temperature soared to a new record high of 82 and stayed warm well into the end of the month. In fact, March 2012 ended up being warmer than April 2012!

Of importance is the lack of warmth THIS March. In fact, we haven’t even been above 50° in the past 15 days! Compare that to 8 days of 60°+ temperatures last March.

Unfortunately, there isn’t much warmth to be had in the next week to ten days. This table shows the different parameters from the National Weather Service’s GFS computer model. If you click on the image, look under the Max-T column to see the high temperatures for the date. It’s very impressive to see the lack of real warmth straight through the model’s last hours: 16 days from now! There’s a real chance we don’t get above 50° until April. -Eric

Posted under climate/climate change, cold blast

The cliche “Oh what a difference a day makes” definitely holds some water this afternoon. Yesterday temps were above 50 in some spots, yet today we are struggling to hang on to temperatures in the low teens as we approach noon. That gives us more than a 30 degree temperature swing when comparing now to yesterday at this time. If 10° doesn’t sound cold enough then let’s talk wind chill. We have had chills in the negative single digits all morning and by tonight they will sink into the negative double digits with actual temps bottoming out near zero. Tomorrow does bring an end to excessive wind, so our high of 20 will actually feel close to 20. -Greg

Posted under cold blast, Wind, winter weather

A streak of 6 straight days at or above 30° comes to a screeching halt today. A cold front moved across the Stateline yesterday afternoon and steadily took our temperatures from near 40 at noon, to the low 30s by early evening. That cooling process continued through the night and we now see ourselves staring 20 degree temperatures in the face through Sunday morning. The cooler airmass is being ushered from the north by a stiff breeze that will remain for the nex 36 hours. Actual temperatures tonight will dip into the teens, wind chills however will be in the low single digits and negatve single digits. Tomorrow a very similar picture is painted with highs in the low 20s and wind chills in the single digits the entire afternoon. This cold spell only lasts for 48 hours though, with highs reaching back into the 30s as soon as Sunday. -Greg

Posted under cold blast, Wind, winter weather