Saturday, May 27, 2017

Drier Weather On the Way

We had a nice start to the weekend with the sunshine and the temperatures in the mid 70°s, but now we've got some rain moving in from the west, currently going through Jo Daviess County.  There were a few thunderstorms embedded in the rain earlier as the rain made its approach, but those storms are dying down.  However, we can't rule out a few rumbles thunder for Jo Daviess while those storms die down.  The rain is tracking northeast, but as it tracks northeast a few showers could skim our counties along the Wisconsin-Illinois border. 

The rain will move out between 9-10pm and we'll get a break from it during the overnight, before more rain moves in around 4am.  The rain will start in from the west, with Jo Daviess, Carroll, and Whiteside counties seeing it first.  Afterwards, it'll filter its way east into our other counties between 4-7am.  A few thunderstorms are possible in Whiteside, Lee, and the southern portions of Dekalb as an upper-level trough will move in tomorrow morning.  The dip in that trough will move in over central Illinois, which is where the instability will be highest.  However, there will be just enough instability in our southern counties to allow for some thunderstorm development. 

All the other counties will see rain, with everything moving out around 4pm when the front moves out.  After the front moves out, we'll see clearing skies for the evening with temperatures staying in the low 70°s.  We hang on to these nice condition for Memorial Day, as well as for the rest of the week.

Friday, May 26, 2017

A Stormy Start, But A Nice End to the Weekend

It hasn't been the nicest end to the work week with all the rain moving through during the entire afternoon, but luckily that has now cleared out.  We stay in the upper 50°s to low 60°s as we head through the evening, and we'll also see the clouds decrease.  By the time we move into the overnight we'll have partly cloudy skies and temperatures in the mid 50°s.  We get a break from the rain through tomorrow afternoon, but we'll have a chance for some thunderstorms starting in the evening around 6 when a low pressure system makes its approach from the plains.  This low is what brought us the rain today, but as it moves closer it'll pull in more warmth and moisture into our area.  This will be nice for most of the day tomorrow with partly cloudy skies and temperatures in the 70°s, but by the time we get to around 6pm we'll see those temperatures warm up even more with the approaching warm front, and this will lead to thunderstorm development.

Most of the thunderstorms will develop to the west and southwest of the Stateline, mainly in eastern Iowa and along the Iowa and Illinois border.  However, since that low will be tracking northeast, we could see a few thunderstorms move into our area during the evening hours.  Furthermore, we'll see more rain occurring during the late-night hours and through the overnight as a cold front will pass through the stateline, but we could also see a few thunderstorms lingering along the front during the overnight as well.

The front will move out Sunday morning around 7am, where we'll stay dry for the rest of the day with partly cloudy skies and temperatures in the mid 70°s.  Along with that, we hang on to the dry and beautiful weather for the rest of the week!

Timing the Rain Friday

It will be a bit damp to kick off the holiday weekend, but not a total washout. Temperatures have been warming quickly this morning, and we will make it into the low 70's this afternoon. Rain moves in around noon to 1pm and will linger through about 5pm. A small but quick ridge moving through has keep some sunshine around this morning but as a shortwave rides along the ridge it breaks down and brings enough lift to support rain and even a few embedded storms.

Most of this evening should be dry and the dry weather will last through Saturday with high temperatures climbing into the upper 70's. Periodic rain chances continue Sunday and Monday.

Thursday, May 25, 2017

Weekend Warmth Brings Rain, but Still an Enjoyable Weekend

Temperatures got a little late day boost as the clouds cleared just in time for a beautiful sunset!  Highs this afternoon reached the upper 60's and low 70's.  Still a little below average, but moving in the right direction.

Most of the evening has been clear, but you may have noticed a little more cloud cover sneaking in from the west.  This is due to an area of low pressure moving through the northern Plains.  There have been a few light showers showing up over Minnesota and northern Iowa, but overall coverage of the rain has been fading with a weak ridge of high pressure over the Great Lakes.

A stronger low pressure system moves in from the southwest Friday afternoon keeping temperatures in the low 70's, but also allowing for a few showers and thunderstorms to develop as early as Noon.  Those showers will last through late afternoon with drier skies expected during the overnight.  Most of Saturday, now, is actually looking dry with a warm front settling south over central and southern Illinois.  A severe weather outbreak is possible over the south-central Plains and mid-Mississippi River Valley Saturday afternoon and evening.  As the low moves closer to Illinois Saturday evening showers and thunderstorms will become possible before moving out by Sunday morning.

Scattered showers and thunderstorms will be possible Sunday and Monday with the heating of the day.  Highs will warm into the upper 60's and low 70's.

Memorial Weekend and the Week Ahead

It's been quite a gray week here in the stateline as we've seen 4 inches of rain alone in the month of May, which is about 1 inch above it's average.  We've seen a meridional pattern in the jet stream, and this is what's been giving us all the rain.  This causes low pressure systems to track northward and more slowly, causing them to stall over a given area.  This low is now stalling over Indiana, which is why we've seen cloudy skies this morning.  The low will begin to track more eastward once the jet stream flow starts to return to normal.  The low will pull some clouds out of our area when it tracks east allowing for more sunshine during the afternoon, which will help bump our temperatures into the low 70°s.

Another low will track into our area tomorrow, this one bringing in a warm front.  The warm inflow will bring a chance for some thunderstorms tomorrow afternoon, mainly for our southern counties.  However, this front will stall over our area during the weekend, bringing everyone in the stateline a chance for thunderstorms Saturday afternoon, but only a rain chance on Sunday.  Sunday, the low will track north and begin to weaken, but once it moves out it'll pull cooler, drier air into our area.  This will cool temperatures into the mid 60°s to start the work week, but more importantly it'll help clear our skies and keep the rain away.

Tuesday, May 23, 2017

May Rainfall Adding Up

Both April and May have proved to be very rainy months.  The cooler and rainy weather during April pushed back the start of spring planting and the excessive rainfall during the month of May caused some farmers to have to go back and replant some of their corn.  According to the Illinois Crop Progress and Condition report from the USDA, farmers continued planting soybeans last week while some others went back to replanting corn.  Corn planted in Illinois is at 89 percent, very near the 5 year average of 90 percent, while soybeans planted is at 48 percent.  This week won't be the ideal week for fieldwork and many will have to dodge the raindrops to get work done outside.

On average, the month of May receives just a little over four inches of rainfall.  So far we've received roughly three and a half.  Note: this does NOT include the rain that fell Tuesday afternoon.  This puts us at a little over 0.80" above where we should be for this time of the month.

Additional showers will fall overnight Tuesday and again on Wednesday.  The overall coverage is expected to remain a little lighter than what it was on Tuesday, but it will continue to push our monthly rainfall total closer and closer to that four inch mark. 

We are actually beginning to enter into one of the rainiest periods for spring and summer with May being the third wettest month out of the year.  June is typically our wettest month, followed by August.  As the atmosphere warms it can actually hold a little more water vapor.  The warmer the atmosphere, the more rain that can fall.  It's also when we tend to get more MCS type storm clusters during the late evening and overnight.

Funnel Clouds Spotted Tuesday Afternoon

Severe weather was not in the forecast or expected to occur, but there were a few reports of small and brief funnel clouds over Iowa and northern Illinois Tuesday afternoon.  Unlike an actual tornado, these funnels very rarely touch the ground or do any damage.  They are actually very similar to 'cold air funnels'.  Cold air funnels occur from weaker circulation occurring in the atmosphere several thousand feet above the surface of the earth.  They tend to form in a cooler air mass, typically behind a cold front or when temperatures aloft are extremely colder than temperatures at the surface of the earth. 

Sometimes there can be just enough circulation throughout the atmosphere to produce these funnels.  And if the air is moist enough, like it was this afternoon with the rainfall, a condensation funnel will be visible.

Here are a few photos of the funnel clouds we received earlier today from Rock City and Davis.

Terry Klever
Davis, IL
Destiny Miller
Davis, IL

Kathy Holste
Rock City, IL