Wednesday, February 5, 2020

Could it be? A snow forecast we can all get behind?

We ran a poll a couple of days ago for Groundhog Day asking whether you were ready for spring or wanted some snow. The results were very close to split among the 500 or so votes. In fact, we might have the best of both worlds on deck!

A very warm (but wet) pattern has gotten us through the first half of the week. But now that we are "post-frontal" (the cold front is shifting east of our area), cold air will mix with the next round of precipitation late Thursday, potentially bringing the snow-lovers out there something pretty to stare at out the window. For those that don't want to bother with it, anything that falls should be relatively harmless. And for those that don't want to figure out how to shuffle the kids on a school day, the impacts should be minimal enough that that won't be an issue come Friday morning! Winner winner, French toast dinner! Let's get into the details.


A cold day is in the cards for Thursday. We may start off with a little light rain in the morning with temperatures near 40 degrees. With an upper level trough approaching, cloud cover sticking around, and northerly wind, temperatures will likely remain steady all day. By mid-afternoon, temperatures aloft will begin to cool as the upper level low/trough moves closer. That trough will also serve as a trigger for the development of precipitation near our area by mid to late afternoon.

An upper level trough (the "valley" in the pressure lines) moves through the area over the next 48 hours according to the mid-day GFS model. That trough is responsible for providing the energy and cold air necessary to produce light snow Thursday evening. (WeatherModels.com)

With temperatures still likely up near 40, initial precip could be a rain/snow mix. But those cooling temperatures aloft will change precipitation over to light snow fairly quickly, despite temperatures still in the mid to upper 30s at ground level. As the sun sets, surface temperatures will cool into the mid 30s as light snow chances continue. The departures of the upper level trough by about midnight will bring precipitation to an end as temperatures approach the freezing mark in the wee hours of Friday morning. So, the high level details:

  • What: Good chance of light snow
  • When: Late afternoon into the overnight hours Thursday (~4pm-2am)
  • How much: Maybe 1/2" on non-asphalt/concrete surfaces (light dusting)
  • "Boom" forecast: 1"
  • "Bust" forecast: Flurries
The Wednesday evening run of the high-res NAM3 model, showing forecast radar between 8am Thursday and 8am Friday. Snow breaks out late in the afternoon near the Mississippi River and continues into the evening hours. (WeatherModels.com)

What impacts are we expecting? Very few. With temperatures above freezing for most, or all, of the event, most snowflakes melt on contact with the ground. I expect it could be pretty to look at in the evening in the street lights, and if it comes down hard enough we could see a dusting on elevated/exposed surfaces and outdoor objects. Roads should remain above freezing and thus will be no worse than wet, even the elevated ones. 

Low temperatures will be just below freezing Friday morning, but even the roads should stay in pretty good shape. There conceivably could be a few slick spots on elevated roads early Friday morning, but that chance is deemed to be very low given the forecast.

There remains some discrepancy between the various computer models, but nearly all produce snowflakes tomorrow evening. This should be just the kind of event that will appease some of the snow-lovers while also not interfering with the activities of those that prefer it never happen! Stay tuned to our social media channels for the latest information throughout the day Thursday.


Erik Proseus
MWN Meteorologist

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Sunday, February 2, 2020

Spring-like weather gives way to rain and a return of cold air

Happy Groundhog Day! Phil did NOT see his shadow, so according to him we will be seeing an early spring! (With a track record of 40% over the past decade, we'll see!) It definitely felt spring-like today with plenty of sunshine and highs around 70! Sadly, this will be our last sunny day for a while. Clouds return Monday with rain chances arriving Monday night and sticking around much of the week. Our highest rain chances will be Tuesday and Wednesday as our next cold front moves through the southeast. Cool temperatures follow behind it dropping highs back into the 40s starting Wednesday.


Monday through Wednesday

A steady south to southwest wind throughout the day on Sunday and into Monday will allow for warm moist air to be advected north from the Gulf of Mexico. With this increased moisture, clouds and rain chances return. Most of the day on Monday should be dry but as more energy moves over our area, showers become more likely later in the evening. Despite the soggy appearance, afternoon highs will still be well above average in the upper 60s. Overnight temperatures will only fall into the upper 50s. The persistent cloud cover will help hold in a lot of the heat from the day. Rain chances increase overnight as the southerly wind continues pushing moisture our way, making it feel very muggy.


Tuesday morning will continue this pattern with scattered showers across the area for most of the day. Temperatures that afternoon will warm into the mid to upper 60s once again. While most of the rain on Tuesday will be driven by the Gulf moisture, the story changes slightly as we head into the evening. A low pressure system will move by to our northwest, dragging a cold front along with it. This front will lead to more shower and storm activity overnight Tuesday.
The GFS model showing surface temperatures at 6pm Tuesday in the mid 60s. (WxBell)
The Storm Prediction Center (SPC) has issued a severe weather outlook for our area for Tuesday night. This puts Memphis just out of the Slight (2/5) Risk. Most of the storms will occur Tuesday night. This system's severe threat is very low; however, a few thunderstorms could become strong to severe. An organized line is not expected for this event. These storms will form along the front and be very messy. The window for the severe activity will be confined to primarily Tuesday evening as cold air fills in quickly behind it.

Severe Weather Outlook for Tuesday 02/04/20. Memphis is in a Marginal (level 1/5) Risk. (NOAA/SPC)
Shower activity will continue throughout the day on Wednesday with a few rumbles of thunder possible. Cold air behind the front will quickly push into the area eliminating any severe threat for Wednesday. Since the front is moving through overnight on Tuesday, it is very likely that our high for Wednesday will occur in the morning. Temperatures will likely be in the mid 40s around lunch time and steadily fall into the upper 30s throughout the afternoon. Sadly clouds and cold showers stick around throughout the evening making Wednesday fairly dreary.

The GFS model showing surface temperatures at 3pm Wednesday near 40 in the metro. (WxBell)
Thursday through Sunday

Clouds continue throughout most of the day on Thursday with a chance at a passing shower. Thursday brings below average temperatures back to our area with afternoon highs only in the mid 40s. Clouds begin to clear out overnight with lows in the upper 30s giving you a chilly start to your Friday. By the afternoon, skies will be a mix of sun and clouds with temperatures near 50. Thankfully squeezing out a cool but pleasant end to the work week. Next weekend looks very seasonable temperature wise. Saturday and Sunday with have lows in the upper 30s with afternoon highs in the low 50s. While much of the weekend will be partly sunny, a few isolated showers cannot be ruled out.


Allison Paige
MWN Meteorologist Intern

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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