Get ready for summer! Officially, the season begins on Friday when the solstice arrives. This means that more of the sun’s rays are pointed toward the Northern Hemisphere. This will also be the weekend with the most daylight of any weekend in the year! On Friday, the sun will rise at 5:20 in the morning and not set until 8:36pm. This will give us 15 hours, 16 minutes, and 26 seconds of daylight to enjoy.

Compare that to the shortest day of 2013 which will arrive this December when we will only receive 9 hours and 5 minutes of daylight! Have I given you enough of a reason to make your outdoor plans for the weekend?

Well, if I have be ready for some extreme warmth. In fact, it looks like we could be seeing back-to-back 90s beginning this weekend. Quite a far cry from the upper 40s and lower 50s coming early Wednesday. If we dip into the 40s in Rockford, it would near the record for the date. But with the beginning of summer comes the serious heat this weekend. With high temperatures in the upper 80s and dewpoints in the 70s, heat index values will be in the 95-100° range!

On top of that, some scattered thunderstorms will be possible. Due to the 40% chance, and the fact that this far out I can’t assure that these will happen after the full daytime heating, I’m going to be a bit conservative with upper 80s. However, if the rain holds off until the afternoons or evenings, leaving the morning hours sunny, some lower to middle 90s will be possible! In other words, this is a HOT airmass! Welcome to summer 2013! -Eric

Posted under climate/climate change, heat wave, science, weather geek

Average Date of Last 32°

Patchy frost is in the forecast for early Sunday morning and again early Monday morning.  And while we are entering the middle of May, frost is not unheard-of this time of year.

In fact, the latest freezing temperature (32°) observed in Rockford over the current climatological period (1981-2010) is May 27th.  Most climate observation sites across northern Illinois are similar, with the exception of Mount Carroll.  Over the past thirty years, the latest freezing temperature observed in that Carroll County community was June 10th!

On average, the last 32° reading in Rockford is April 27th.  It is interesting to note that in 2013, Rockford has not fallen to 32° since April 26th!  But that could change, since temperatures are expected to fall into the lower 30s both Sunday and Monday morning.  Climatologically speaking, the chance to see such chilly temperatures will continue to decline.  Nine times out of ten, we won’t see temperatures fall below the freezing mark any later than May 14th. -Joe

Posted under 13 Climate Authority, climate/climate change, statistics, weather

A good indicator when farmers can get in their fields is the soil temperature. Once the temperature of the first four inches of soil reached 50 degrees, seeds are warm enough to germinate.

According to the United States Department of Agriculture (USDA), soil temperatures are 55-60 degrees for most of Northern Illinois with Southern Wisconsin exceeding that 50 degree mark.

So why are we so far behind in planting this year? Too much rain! Imagine that! After a significant drought last year, we are getting too much rainall this year! In fact, some spots in the Midwest saw their rainiest April on record! While our drought is officially over, it continues across the Plains States from South Dakota down into much of Texas.

On average, Illinois farmers are about half way through planting. However this year due to extreme rainfall, only 7% of the corn has been planted.

In Wisconsin, only 4% of the state’s corn has been planted with the average being 26%. Continued dry weather will ensure the number goes up, but rainfall is in the forecast for Illinois and Wisconsin Thursday. Some locations in Northern Illinois could receive in excess of an inch. Wisconsin will remain a bit drier.

Looking at statistics from the USDA for the nation: 12% of the corn is planted which is the slowest pace since 1984. It is very similar to  1993 when much of the Midwest was dealing with record flooding. -Eric

Posted under climate/climate change, drought, flooding, news

April has been quite a rainy month so far with 1.75 inches falling at the Chicago/Rockford Int’l Airport through 3pm Wednesday. That amount is 160% of normal! While 2/3 of an inch of rain falling as a surplus is a good thing to bring our drought to an end, the forecast is not.

The forecast from the National Weather Service’s GFS model shows 2.41″ of rainfall coming in the next 16 days. That amount is more than we should receive in a typical April, 135% of normal.

Of concern is this pattern of repeated rainfall. With our rivers now flooding in Northern Illinois and Southern Wisconsin, we need this pattern to change in order to get the river levels to level off.

Meteorologists refer to this type of situation as ”high evaporative feedback.” Because our ground is saturated, it will lead to increased evaporation in the days and weeks to come. This will cause storm systems to be wetter than normal, with our models possibly underdoing the rain forecast for the next few weeks. Signals show this pattern will persist for a few weeks, possibly well into May.

With a barrage of storm systems coming through the center part of the United States over the next 1-2 weeks, prepare for rising river levels and increased flooding. Below are a few of the river gauges from this afternoon. You can see all of the levels on the National Weather Service’s Rivers and Lakes Page here.  

Posted under climate/climate change, flooding, rain, record weather, safety, science, weather geek

Now that March is finally behind us, let’s take a peek at a few April statistics.

The average high temperature for April 1st is 55 degrees with a low of 33 degrees. It sure feels like April was playing a nasty joke on us for April Fools Day today, we were a little over 15 degrees cooler than normal today. Good news is temperatures are trending upward for the rest of the work week and into the weekend. The average high for the last day of the month is 67 degrees with a low of 43 degrees, so there is something to look forward to!

The GFS model forecasts out 16 days and is currently showing the middle of April to have near normal temperatures. Average mid-April temperatures are right around 60 degrees. Now, this forecast is still quite a ways out BUT there is a light at the end of the tunnel! A record high temperature of 93 degrees was set back in 1930 and a record low of 5 degrees set in 1982, however the climate outlook isn’t putting any extremes in our forecast this month. The Climate Prediction Center is showing an average temperature and precipitation trend for the month of April. The GFS 16 day outlook is giving Rockford a potentially wetter than average first half of the month. On the bright side, more April showers brings more May flowers, right? The average precipitation for April is 3.35 inches of rain and 0.9 inches of snow.

A few facts and a small glance at the GFS long range forecast for April. Let’s hope this month is closer to average than the last!

Posted under 13 Climate Authority, climate/climate change, rain, record weather, snow, statistics, weather

Here’s a glance at Rockford’s March 2013 one last time.

If you can believe it, the normal high temperature for Rockford in March is 46.9 degrees. Sadly, March of 2013 brought us an average high almost 10 degrees cooler at 37 degrees. Our average low temperature followed the same trend, being 5.4 degrees cooler than normal. We actually only had 4 days with average temperatures above 40 degrees! What’s even more interesting is that Rockford averages 4 or 5 days of 60+ degrees in March, but this year we had ZERO! As a matter of fact, almost one third of our high temperatures and 94% of our low temperatures were below freezing! Here are two facts we can put some blame on for those cool temperatures: 1) 15 out of 31 days had an average wind flow out of the northwest. 2) 16 out of 31 days averaged cloudy skies.

Now, let’s talk about snow. Finally, a category we were above average in! On March 5th, 2013, Rockford received 9.6 inches of snowfall, crushing the previous record of 5.4 inches back in 1959. Actually, the average snowfall for March in Rockford is 4.8 inches- we almost tripled that! This March, we received 13.9 inches of snowfall. Not to mention, Rockford recorded precipitation for 21 out of 31 days!

Now we can finally say goodbye to cold, snowy March as we spring into April.

Posted under 13 Climate Authority, climate/climate change, record weather, snow, statistics, weather, winter weather

According to the United States Drought Monitor, Northern Illinois is still abnormally dry and the rest of Illinois is currently not under drought conditions.

Just three months ago, 78% of Illinois was abnormally dry, while 40% was under moderate drought conditions, and 9% (including us) under severe! We can thank those “spring” snow storms, along with the January and February rain and snow showers for pulling all but 16% of Illinois out of dry conditions.

We’ve actually had an excess of precipitation since the start of the year, compared to our normal of 4.82 inches for January, February, and March here in Rockford. January brought us 3.09 inches, slightly less from February at 2.98 inches, and just over 2 and a quarter inches so far this month. These precipitation amounts total to 8.36 inches and nearly double our precipitation totals for the same three months in 2012 (4.63 inches).

There is a little bit of rain and rain/snow mix in the forecast for the weekend, so don’t forget to check the updated U.S. Drought Monitor on Thursday. In the meantime, Northern Illinois will slowly chip away those abnormally dry conditions.

Posted under 13 Climate Authority, climate/climate change, drought, statistics, weather

There is more snow on the ground today, than any March 26th back through 2003! (Unfortunately, our resources only allow us to go back ten years when it comes to snow cover.) Right now, 46.6% of the contiguous 48 states is covered by snow. Last year at this time only 7.4% of the country had snow on the ground. The ten year average is just 23.8%.

Snow cover is important to look at when you’re forecasting weather patterns. Snow reflects much of the sun’s incoming rays, keeping the air closest to the ground cool. Until the snow on the ground really melts in the center part of the country, our chance of seeing a real significant warm up (60s and 70s) will be slim to none.

Posted under climate/climate change, snow

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

March 20 marks the vernal equinox, although the weather may not feel much like spring with cooler than average temperatures in many parts of the country.

The conditions couldn’t be more different than last year this time. By March 19, 2012, more than 2,200 warm-temperature records had been set or tied across the U.S. That is about 1,000 more than have been set or tied so far this March. By comparison, this month feels like a dud. Temperatures have been much closer to normal this year, and more than a few winter storms have crept their way towards the first day of spring.

The graph above shows the month-to-date temperature anomaly in Rockford for March 2012 (red) and March 2013 (green). As you can see, 2012 was significantly warmer than usual at this time of year, while March of 2013 has actually been a little colder than normal.

The maps below show the difference between these two months across the country. Areas like the Southeast and Midwest are cooler than they were last year, while regions like the West and Southwest are considerably warmer.

All told, 2013 is much closer to an average year than 2012 was. NOAA releases its annual spring outlook on Thursday.

Posted under climate/climate change