Showing posts with label Harvey. Show all posts
Showing posts with label Harvey. Show all posts

Wednesday, August 30, 2017

What to expect from Harvey in the Mid-South on Thursday

The remnants of former Hurricane Harvey will move right over the Mid-South on Thursday and Thursday night. This 7-minute video will describe the impacts expected. Slides used are included below for those unable to view the video.








Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Tuesday, August 29, 2017

Harvey pays a visit to the Mid-South

After watching Harvey decimate a large portion of southeast TX, the storm has finally started shifting northeast. In its sights... the Mid-South. Fortunately nothing like what occurred in Houston and surrounding areas will occur here, but we'll definitely feel the effects. Let's get into it.


A Flash Flood Watch will go into effect Wednesday afternoon and continue into Friday. The initial feed band of showers and a few thunderstorms will arrive Wednesday morning, though it won't be the main event. However, as with any rain originating from a tropical system, downpours are likely. By afternoon, we'll be in a pattern favoring scattered showers and thunderstorms, though it won't be a washout.

Rain chances will go up dramatically Wednesday night, especially as we approach Thursday morning. Heavy rain chances go up and the wind will start to pick up a bit, increasing to about 15 mph from the east. Thursday is "Washout Day" as the heaviest of the rain on the north side of the storm moves over the region. A couple of inches of rain are likely Thursday with very heavy rainfall rates in convective bands that sweep through. Wind will increase during the day and become gusty to 25-30 mph. Flash flooding becomes more likely in areas prone to ponding and flooding, especially in the concrete jungle.

The American GFS model shows precipitation moving into the Mid-South Wednesday with heavy rain Wednesday night into Thursday evening. This model, along with several others, predict dry conditions on Friday. (WxBell)

By Thursday night, as the Memphis Tigers open their season at the Liberty Bowl against Louisiana-Monroe at 8pm, rain will still be falling but models are starting to indicate that the rain may be tapering as the evening goes on, as low pressure from Harvey moves near or just east of the metro. As the vast majority of the heavy rain will be north and west of the low, once the low passes by to our north, rain chances drop quickly. So besides rooting for the Tigers, we need to root for a faster motion of the low! Wind will shift to the north but remain gusty to 30+ mph Thursday evening. The other potentially good news is that the primary threat from isolated spin-up tornadoes is east of the low, therefore that threat appears to be minimized in the metro.

The National Hurricane Center estimated rainfall from Harvey through Friday evening. A heavy band of 6"+ is forecast to set up from the metro northeast into western KY. (NHC)

The GFS model's predicted total rainfall through Friday evening shows the same band of heavier rain as NHC with 3-5" across the metro. (WxBell)

As far as preparation, plan ahead for significant rainfall Wednesday night through Thursday night with the potential for flash flooding and urban flooding. Make sure storm drains are cleared tomorrow around your home. Also you will want to secure lightweight objects outdoors that could blow around in 30-35 mph wind.

Looking ahead, with the faster motion of Harvey, we look to be drying out heading into the holiday weekend! In fact, Friday could end up being dry but breezy with comfortable temperatures. The Labor Day weekend looks great weather-wise with highs in the 80s and dry conditions. The next chance of rain arrives Tuesday with another frontal system reinforcing the below average temperatures we've experienced for most of August.

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook, Twitter, and Google+
Visit MemphisWeather.net on the web or m.memphisweather.net on your mobile phone.
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

Friday, August 25, 2017

Is summer over? And will Harvey visit the Mid-South?

While the summer was not overly hot, it seems a lot of folks are still ready to put it to bed earlier than it's ready to go. Kind of like a middle schooler and her parents. (I know, trust me...)

Yet here we are with a week left in August, knowing that we've historically had some hot Septembers, basking in early fall weather featuring low humidity, not-too-hot highs in the mid 80s, and very comfortable mornings in the 60s. Of course, that begs the questions - "Is summer over?" "Have we seen our last 90° day?"

Well, our forecast has no 90°+ highs through the end of August. And the week 2 outlook from NOAA for the first week in September (below) gives us a high chance of below normal temperatures. Indeed, even the long-range model outlooks show a decent chance of below, or perhaps near, average temperatures into the middle of September.

The 8-14 day temperature outlook from NOAA shows a good chance (nearly 50%) that we will experience below average temperatures for the first week of September. (NOAA)

By the time we get to mid-September, average temperatures are about where they are right now - in the mid 80s in the afternoon and mid 60s in the morning. In other words, the "expected" trend here is for roughly this temperature patter to continue for the foreseeable future. Does that mean we won't reach 90° again? No. But as we get towards early fall, the likelihood of dewpoints that cause a 90° day to feel like 100° is also not that high.

In other words, even if we get a "warm" day that sees a high temperature that starts with 9, it probably will be just that - a pretty warm day, but not a sweltering one.  A couple of facts: record high temperatures at or above 90° have occurred into mid-October, and the average last 90° day is September 19. We aren't there yet!

What about Harvey?

Nationally, all weather eyes are trained on the Texas coast as Hurricane Harvey. With wind speeds bumping category 3 strength and minimum pressure, expected storm surge, and forecast rainfall on a category 4-5 level, it's worth your attention.

Exploding from a Tropical Depression Wednesday night to a category 2 storm last night, Harvey is ready to make its presence known over southern and eastern Texas and at least the west half of Louisiana. Projected rainfall amounts are ark-worthy, which I find particularly disturbing for Texas, where sometimes everything does seem bigger. I fear the images we see from the Lone Star State this weekend, and continuing into early next week, will be unconscionable. The battering that the coastline and near-shore areas take from 100+ mph wind and storm surge that is higher than any person alive is tall could somehow be overshadowed by the two to three FEET of rain that falls across parts of the region.

Forecast rainfall over the next week from Harvey. Houston metro is included in the 20"+ area, resulting in a total of over 5 million people forecast to receive 20" of rain. (NHC)

As hard as it is to predict, lives will unfortunately be lost. And in case you wonder, meteorologists can gawk at the data all day, but those with a heart don't root for the weather, we root for the people and we think about them when using words like these to describe likely impacts:


I'll leave the reporting and forecasting for those areas to our south to other experts in those areas. However, this will be a long-lived, high-impact system. It will take days to move out of the central Gulf Coast region, which makes the forecast for Memphis and surrounding areas that much more difficult. For more information, visit the MWN Tropical Page.

The forecast track of Harvey valid at 1pm Friday. Notice after landfall that it barely moves through early next week. (NHC)
That said, the most reliable medium-range forecast models that we employ do, in fact, move the remnants to the northeast. We will see high clouds over the area this weekend, but dry conditions continuing with moderately low humidity and highs in the 85-88° range. By early next week, a front will drop into the area, but with limited moisture to work with, rain chances will be spotty. Scattered showers and perhaps a few thunderstorms are possible early in the week. By mid-week, things become a bit more uncertain depending on the ultimate track of Harvey's remnants. For now, I'm including elevated rain chances for the mid/late week period. There is a potential for very heavy rain if the remnants move close by. Too soon to tell...



Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook, Twitter, and Google+
Visit MemphisWeather.net on the web or m.memphisweather.net on your mobile phone.
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