Sunday, April 21, 2019

First 80 Degree Day of the Season

Plenty of sunshine and warmth Sunday afternoon pushed temperatures across northern Illinois and southern Wisconsin into the upper 70s and low 80s.  Rockford reached 80 degrees for the first time this season/year. 

This actually isn't too far from when we typically achieve our first 80 degree day.  The long-term average for the first 80 degree day in Rockford typically occurs on or around Aprill 22nd.  The last time the temperature was 80 degrees, or higher, was last October 7th, 2018.
The earliest the temperature has reached 80 degrees was back on March 15th, 2012.  The latest Rockford ever reached 80 degrees was June 1st, 1973.

Monday will be another warm, summer-like, afternoon.  A little more cloud cover during the afternoon will keep temperatures from hitting the 80 degree mark, but highs should warm into the mid and upper 70s.  Showers and thunderstorms will be possible ahead of a cold front late afternoon and evening.

Saturday, April 20, 2019

Warm Easter Sunday

Winds shifting around to the south Sunday morning will give temperatures a nice little boost during the afternoon, bringing highs into the mid and upper 70s!

High pressure centered over the western Great Lakes Saturday left most of the Midwest with northing but sunshine and warmth.  Officially the high in Rockford reached 68 degrees!  Clear skies continue into Easter Sunday morning with temperatures starting off in the mid 40s. 

Winds will increase a little during the afternoon pulling in a very warm air mass.  This will bring temperatures into the mid 70s for most, if not the upper 70s to near 80 degrees Sunday afternoon.  Since Easter doesn't fall on the same day every year there is no 'normal high' for that day.  The warmest Easter day ever recorded was April 12th, 1925 and April 10th, 1977 when the temperature reached 84 degrees.  Last year Easter fell on April 1st and the high temperature that afternoon was only 32 degrees.

Thursday, April 18, 2019

Breezy Today, Windy Tomorrow!

It took a while for thunderstorms to break through the cap and materialize yesterday. We dodged the severe weather threat as only a few strong storms formed right after sunset and moved into Southern Wisconsin. As we were all waking up this morning, a cold front was making its way through the Stateline. This has set the stage for a chilly, cloudy, and breezy day for the Stateline. 
We have been mostly cloudy and breezy for most of our Thursday morning. A recent look at satellite and radar shows a band of showers now moving through the eastern half of the viewing area. This is all due to a upper-level trough that is currently moving through the Great Plains. The shower activity should decline as we head into this afternoon. but a shower or two still cannot be ruled out.
Did you enjoy the 75° temperatures yesterday? Well, we are sad to say that today is going to feel the total opposite. With the passing of this mornings cold front, temperatures will be fluctuating in the upper 40's-low 50's throughout the afternoon. Not only that, its going to be breezy as there will be an uptick in winds this afternoon. Winds will gust out of the northwest at 20 to 25 mph at times.
Now heading into Friday, a low pressure system will slowly track southeast of the region to start of the morning. This low will strengthen and deepen causing a tight pressure gradient at the surface. The tighter the pressure gradient is, the stronger the wind gusts. Tomorrow, we can expect wind gusts a little bit stronger than today. Temperatures stay below average as well making it a chilly and windy start to the weekend.

Wednesday, April 17, 2019

Isolated Thunderstorm Wednesday Evening - Severe Threat Quickly Ending

 9:10pm Update: Our overall severe threat has pretty much come and gone Wednesday evening.  While an isolated strong/severe storm can't be ruled out only a few showers and isolated storms are expected during the overnight. 

Storms over the southern Plains will lift northeast after Midnight impact parts of central Illinois early Thursday morning.  Those could produce some gusty winds but the biggest threat looks to remain south of I-80.  A few showers will last into Thursday morning with mostly cloudy skies expected Thursday afternoon.

Isolated thunderstorms have developed Wednesday evening over northern Illinois and southern Wisconsin.  The storms have remained below severe limits, but did produce pea to penny sized hail in Beloit and South Beloit.

Isolated thunderstorms continue to move east of I-39 this evening with a line of weakening showers and thunderstorms moving into eastern Iowa.  The severe threat continues to quickly decrease this evening as a cold front advances from the west.

Thunderstorms developing over the southern Plains will lift northeast overnight into central Illinois.  These storms will pose a wind threat but mostly south of the area and are expected to move in after Midnight.  A few showers will linger into Thursday with temperatures holding steady in the mid and upper 50s.

Severe Potential Later Today

After almost having a "sunny & 75" forecast yesterday, our attention turns to the potential for thunderstorms this evening. The Storm Prediction Center (SPC) in Norman, OK has placed the Western half of the Stateline is under a Slight Risk, while the other is under a Marginal Risk. Now, don't pay attention to the category. Just know that there is the potential for severe weather throughout this afternoon and evening.

There are two key features that we need to keep an eye on for today's severe weather potential. The first is the stationary front in central Illinois, and the second is a low pressure system out in the Midwest. Models continue to show this stationary boundary lifting northward as a warm front. If this does occur, the viewing area will be placed in the warm sector of the low pressure system. This is where a large amount of moisture and warmer air is brought up from the south. This will provide a potent environment for severe storms to form. With that said, if the warm front fails to lift north and stays to our south, than that drops our severe weather chances drastically.

There's one other factor into whether we will encounter severe storms this evening. It's something meteorologists call "the cap". Normally, temperatures decrease the further up you go in the atmosphere. But sometimes, there will be layer of relatively warm air aloft, usually several thousand feet above the surface. This acts as a blocker and delays the development of thunderstorms. 

Thunderstorms rising into this warm layer become much cooler than the surrounding air, which inhibits their ability to rise and fully mature.If thunderstorms can break "the cap" this afternoon, the severe weather potential for our area will increase.

The time frame in which we have the best chance to see severe thunderstorms will be from 4 PM to 11 PM. Storms will initially develope out to our west. They will then move in during the evening commute, so make sure you take your time heading home this evening. Most likely will see gusty winds and large hail, but a tornado or two cannot be ruled out!

And with severe weather in mind, here are a few severe weather safety tips. Always have multiple ways to receive watches and warnings issued by the National Weather Service. That could be with a weather radio, your local meteorologist, or on your cell phone. Then, make sure that you have a safe place and a severe weather kit ready to go!

Tuesday, April 16, 2019

Sunny & Dry Before the Storms Roll In

We had a bit of a wet start to our Tuesday as a few scattered showers came in from the west and quickly passed through the Stateline. These showers were very light in intensity and wasn't heavy enough to cause slick conditions on the roadways. Once they passed well off to the east, sinking air in the atmosphere caused a few breaks in the clouds allowing some sunshine to peek through.

With the suns help and also light winds out of the south, temperatures this morning have already risen into the 50s. High temperatures this afternoon will top out in the mid to upper 60's. Enjoy the dry weather now, because we will see rain and thunderstorm chances in the forecast during the next 3 days.

The Storm Prediction Center has our entire viewing area in a Marginal Risk. A marginal risk is the lowest category (level 1 of 5) for severe weather. A higher threat for severe weather persist to the southwest in the Enhanced Risk (level 3 of 5) that stretches over portions of Oklahoma, Texas, and Arkansas. This is where you have the right conditions for tornadoes to form.

For us in the Stateline, a warm front will lift over the region tonight into tomorrow morning. This frontal boundary could spark up a few showers during the overnight hours. This places our northern Illinois counties within the warm sector of the mid-latitude cyclone.

The warm sector is the area between the warm front and the cold front. This will set the stage for an abundance amount of warm moist air to be pulled in from the south. Creating a prime environment for showers and thunderstorms to form.

Our best chance for severe thunderstorms comes between Wednesday evening and Thursday morning. The tornado risk is low, but we do have a good chance to see heavy downpours, small hail, and gusty winds. Remember to have a multiple ways to receive watches and warnings during a severe weather event!

Monday, April 15, 2019

Sunshine to Start, Chance for Afternoon Showers

This morning, the sun had risen over the snow covered ground across the Stateline. The further east you are, the more snow you received from yesterday's "over performing" snowstorm.

From yesterday's snowstorm, the Rockford Airport recorded 2.9" of snow. That is now the 5th largest snowfall accumulation recorded on record during the month of April. The good news is, the the combination of the sunshine and warmer temperatures today should melt a good chunk of it.

We are starting off out Monday morning with plenty of sunshine and chilly temperatures. Lows this morning dropped down into the upper 20's and lower 30's. In fact, Rochelle dropped down to 13° this morning.

But this sunshine will give way to increasing clouds this afternoon as a weak disturbance moves in from the west. This disturbance will also bring a slight chance for some showers around mid to late afternoon. So it wouldn't be a bad idea to have an umbrella on hand if you re heading out today. High's today will climb to around 50's which is still below average. But we climb above average the next three days with high's in the upper 60's.