Sunday, July 29, 2018

Elevated rain chances, then more pleasant summer weather ahead!

The Mid-South experienced a couple of days of near to slightly below average temperature and humidity days this weekend and now we look ahead to the upcoming week, which had been promising a wet start then more decent weather to end the week. Let's see if that has changed any given the latest computer data and current state of the atmosphere.

Tonight

We head into Sunday night in-between any major systems as weak high pressure controls much of the eastern U.S., but low pressure is forming to our west. At the upper levels, a disturbance in the force will move across the area through the first half of the night, leading to a chance of a few showers, mainly in northeast AR. A much more moisture-rich airmass sits to our south, but will start to move north tonight as a stationary front lifts into our area by Monday. Temperatures will be near average in the lower 70s.
Late afternoon runs of the HRRR model show the potential for scattered showers and thunderstorms through the evening hours before drying out overnight into Monday morning. (weathermodels.com)

Monday

Monday brings another late day pocket of upper-level energy across the area, so while much of the day should be dry, more scattered showers and thunderstorms are possible by late afternoon and evening. They will tap into a more humid and unsettled airmass with the surface front nearby, so a couple of storms could be strong. The Storm Prediction Center currently has us in a Marginal Risk (level 1/5) for severe weather, though high-resolution models indicate that the prime area of concern for storms could slip by to our south and west. Expect highs to be below normal - in the mid to upper 80s.

The mid-day run of the high-res NAM model forecasts a few evening showers tonight then a lull before more showers and storms moves through late afternoon/evening on Monday. The heaviest storms should swing through southern AR if it is accurate. (weathermodels.com)
 
A Marginal Risk (level 1/5) of severe storms is forecast for a broad area from the Ohio Valley southwest into the Arklatex on Monday. A few storms could having strong wind gusts in the PM hours in the Mid-South.

Monday night - Tuesday

On Monday night, expectations are for a wetter pattern with weak low pressure moving along the front draped over the area. That said, the latest model data has been trending a little drier than we had thought late last week. We're still going with "likely" for the rain chances, but it may not be as heavy or prolonged as first thought. By Tuesday, an upper level trough will form over the Midwest and Mississippi Valley, which will begin to shove the cold front to our east. Once again, there is a chance of scattered showers and thunderstorms, but the severe threat appears minimal and rain chances move east with the cold front as the day goes on. We should be dry by Tuesday night. Another "cool" day to end July with highs in the mid 80s.

Forecast rainfall from the National Weather Service through this week's event is generally 1/2"-1", though amounts could vary quite a bit in any given spot. (WeatherBell)

Mid-week and beyond

For the rest of the week, the upper level trough hangs on over the Mississippi Valley region it appears, which should keep most or all of the precipitation to our east. It also means more pleasant weather is likely, especially for mid-week as August begins. We'll certainly take that! The long-range outlooks from last week pointed to a period of below average temperatures to end July and start August and it looks like they were accurate. Look for highs in the 80s to continue!

The setup in the mid levels of the atmosphere by Wednesday morning features a large trough of low pressure controlling our weather with a well-entrenched high over the southwest U.S. and another high off the Atlantic coastline. Showers and thunderstorms are expected ahead (to the east) of the trough over us with cooler weather under the trough. (PivotalWx)
Expect dry weather to continue as well through the end of the week with temperatures moderating and humidity below summer norms with dewpoints in the 60s. Signs point to near-average conditions heading into next weekend and the first full week of August as many Mid-South kids and teachers get ready to head back to school!





Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
Download our iPhone or Android apps, featuring StormWatch+ severe weather alerts!
MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Wednesday, July 25, 2018

Unbearable summer heat looks to remain at bay

It has felt pretty decent outside recently for mid-July if you ask me. What's been causing all of this nice weather? Well a couple of things. One of the key factors for us lately is we haven't been stuck under a ridge pattern. When we get into these patterns, it keeps out any fronts that would help out our temperatures. This leads to extremely hot temperatures, increases those pesky pop-up afternoon shower chances, and makes dewpoints sore through the roof.


Thankfully, in recent times an upper-level trough has in control for the most part over our area. This allows temps to stay fairly mild for mid-July, holds dewpoints in the 60s, and keeps those afternoon thunderstorms away. Looking at the next few days Mother Nature will try to bring those sticky dewpoints back into the picture, but another cold front will pass through on Friday, which will help to cool things off again.


A little sticky and gross tomorrow

Tomorrow is likely going to be the most summer-like day that we will see this entire week. Highs will reach around 93 by the afternoon with heat index values creeping near the 100 degree mark. Winds will remain out of the northwest, which will keep dewpoints at bay and in the upper 60s.

While it will probably feel a bit more sticky tomorrow, there will not be enough moisture for afternoon pop-up thunderstorms to be a concern. So, lucky for us, we should dodge showers for yet another day.


Cold front Friday sets the stage for a fantastic weekend

Beginning tomorrow night, cloud coverage and our rain chances will begin to increase ahead of Friday's cold front. As the front moves close to the Mid-South, this may provide enough forcing to get some showers and maybe even a thunderstorm or two to develop.

Timing of these showers appears to be between late Thursday night through Friday morning. Different models have different variations on timing of these showers, but since they appear to be moving when temperatures are naturally at their coolest, there are no severe weather concerns.

The NAM model shows a line of showers passing through sometime during the overnight hours on Thursday night and showers moving out of our area rather quickly on Friday. (Tropical Tidbits)
Since these showers do appear to move through in the AM hours, afternoon and evening plans appear to be in the clear, but we'll be closely monitoring that. Additionally, cloud coverage through the day on Friday will keep high temperatures in the mid 80s. That's right, mid 80s. 


Saturday looks fantastic. If you have weekend plans, definitely make sure they include Saturday. Highs near 90, dewpoints in the mid 60s, basically no rain chances - sounds great to me!

Sunday looks to be very similar to Saturday in terms of temperatures; however, some rain chances may try to creep in the afternoon and evening. I am still not completely convinced that showers will arrive Sunday and not Monday, but with that being said Sunday night into Monday do appear to be rather wet compared to recent days. 

Cooler temps are here to stay for now 

The past week has been pretty refreshing with temps remaining slightly below normal. Luckily, this is expected to continue into next week and weekend. While daily high and lows may vary, our 6 to 10 day outlooks give us a high chance of remaining below average for our temperatures and slightly above average for precipitation.

The Climate Prediction Center keeps the Mid-South in below normal temperatures from next Tuesday through next Saturday. (NOAA/CPC)
The Climate Prediction Center keeps the Mid-South on the cusp between normal and slightly above normal in terms of precipitation. (NOAA/CPC)


Caroline MacDonald
MWN Meteorologist Intern

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
Download our iPhone or Android apps, featuring StormWatch+ severe weather alerts!
MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder