Tropical Weather Update

May 28, 2022

I hope everyone is having a good weekend. It's time to start watching the tropics a little closer, the NHC is showing a 20% chance of development through 5 days for the southern Gulf. The synopsis is that we may see a tropical system in the Gulf or Caribbean sometime next week. The main threat would be some windy and rainy weather, worse case a tropical storm, for southern or central Florida or Cuba and the Bahamas. Currently there is no threat for the northern Gulf. Read on for more details.

The NHC is tracking the first named storm in the Eastern Pacific, Tropical Storm Agatha. You can see the track below. Agatha will make landfall in southern Mexico as perhaps a category 2 hurricane on Monday. 

The storm's remnants will then cross Mexico/Central America and enter the Bay of Campeche or western Caribbean sometime around the middle to the end of next week. There is enough heat in the water to support development but right now chances for significant development look pretty low. Wind shear (which is detrimental to tropical cyclone formation) is forecast to be fairly strong during this time. Models are not agreeing on a solution at this point. The Euro has an east-weighted storm developing in the Bay of Campeche or Yucatan Channel around Thursday or Friday with it then moving ashore, maybe as a tropical storm, somewhere along the Central or Southern Florida Gulf Coast Sunday or Monday. The GFS's solution is a bit more complicated. It has the remnants of Agatha kick starting a Central American Gyre (CAG). The CAG is a broad area of rotation that can form this time of year over Central America. CAGs can sometimes provide the seed needed to start tropical development. To be honest I'm not sure if the remnants of a storm can start a CAG or if it is due to some other influence. Nonetheless, the GFS shows a CAG forming and spitting out a tropical system south of Cuba Thursday or Friday with a tropical storm then moving off to the northeast across Cuba and the Bahamas. The Euro and GFS ensemble members largely agree with the operational models. For what it's worth the Canadian model and its ensembles are in agreement with the Euro. Despite this agreement it is too soon to tell what if anything may happen. 

Bottom line is we're looking at tropical storm strength at the most and at this point I'd say a tropical depression or some kind of messy low pressure is more likely. Again, the northern Gulf is not at risk at all at this point. This is probably too many words for something that is most likely going to be a rainmaker for places to our south, but I know any kind of tropical activity in the Gulf tends to cause excitement.

Enjoy the rest of the Memorial Day weekend, don't forget to take a moment and remember what the day is for. We'll start to get a clearer picture around midweek. Once this system is out of the picture there are some hints that there may be something else to watch around the first full week of June.

Chris

Chance of Severe Weather Today and Tomorrow

May 25, 2022

It still looks like this stormy pattern will clear out by the weekend but before it does there's a chance of severe weather today and tomorrow as a front pushes through. Parts of our area have a marginal risk for severe weather both days with all modes (damaging winds, tornadoes, and hail) possible, albeit with low chances for each. Damaging winds will be the most common threat but an isolated tornado and hail are also possible. Expect stormy weather to continue off and on, sometimes steady, until Friday morning or so with a small chance for severe weather with each round. Rainfall totals could get fairly high in some areas.

Day 1 (7 a.m. today through 7 a.m. tomorrow)

Day 2 (7 a.m. tomorrow through 7 a.m. Friday)

Estimated rainfall through Saturday morning

We're more or less done with the main threat of severe weather for the season outside of a tropical cyclone or a strong summer thunderstorm. There have been several days over the last few weeks where parts of our area had a marginal risk for severe weather but I didn't send an email because tornadoes typically weren't in the forecast or were for only a small area with a low chance. With the widespread, although low probably, nature of this event I thought I should let you know what to expect the next few days.

That's it for today. Nothing to be concerned about in the tropics although the Eastern Pacific is heating up a bit. We'll see if the Caribbean picks up in a week or two.

Chris

Update on the Tropics

May 22, 2022

Synopsis: expect stormy weather the rest of the week, hopefully clear(ish) by the weekend. The NHC has identified an area with a 10% chance of development that's nothing to worry about. In the longer term, models are hinting again at development in the western Caribbean around the end of May or first week of June.

In depth: I hope you all are enjoying the weekend, here are some more details for those that are interested. Saturday was pretty nice right along the immediate coast but there was some scattered stormy weather inland through the rest of the region. Then this morning storms associated with a system in the northern Gulf moved inland with more to come. There is a marginal chance for severe weather today and tomorrow with the main hazard being damaging winds, although an isolated tornado right along the coast can't be ruled out. We're just about to get another strong squall along the coast anytime now.

I'll get to it in a moment, but this system has been given a 10% chance of development by the NHC. This system is being drawn north ahead of a front that is going to remain stalled through MS, AL, and GA until midweek. On Wednesday another cold front approaching from the west will lift this stalled front north as a warm front before it sweeps through Thursday. Hopefully the weather will clear out by the weekend but we may see some coastal showers Saturday and a greater chance on Sunday. Bottom line, expect a wet week off and on, potential rainfall totals through Friday morning are below.

Getting back to the tropics, the potential system I wrote about last weekend never materialized (what we're seeing in the Gulf now is unrelated). This system in the Gulf is just one of those things that pops unexpectedly up from time to time. I say unexpectedly, but since we're getting close to the beginning of hurricane season this is the weather pattern we get from time to time. I don't think this system has enough time over water to develop and wind shear to the west is a bit strong, but there is a bit of low level rotation that you can see on satellite. Nothing to be concerned about, I'm really a bit surprised that the NHC put it on their outlook but they are the experts.

Day cloud phase satellite loop. Cooler/bluer colors are low level clouds, warmer/redder colors are upper level clouds.

Looking out to the end of May and first week of June the GFS, Euro, and Canadian ensembles are hinting at tropical development in the Eastern Pacific and western Caribbean. Since the operational GFS, Euro, and Canadian models are also showing development in the East Pac, I'd say that is the most likely solution at least at first (for a refresher on the difference between operational and ensemble models, see this post). Sometimes Eastern Pacific development portends development in the Caribbean as the area of favorable conditions can move from west to east, we'll just have to wait and see. Bottom line is that there's nothing to be concerned about but we're at that time of year where we need to keep an eye on things.

Have a good week.

Chris

NHC Tropical Outlooks Start Today - We May See an Early Start to the Season

May 15, 2022

Here we are at the first tropical weather post for the 2022 season. While hurricane season doesn't officially begin until June 1st, a few years ago the National Hurricane Center started issuing the first outlook of the season on May 15th due to the early season activity that's been occurring. All you really need to know is shown on the NHC 5-Day Outlook below, no activity expected. The rest of this post will cover the expectations for the season as a whole and the potential for early season activity in the Caribbean starting as early as next Friday.

This year is expected to be another above average season. Colorado State University (https://tropical.colostate.edu/forecasting.html) is calling for 19 named storms, 9 hurricanes, and 4 major hurricanes (category 3 or stronger). Florida (the whole state) has a 96% chance of a named storm impact with the northern Gulf Coast counties in the 50% range (https://tropical.colostate.edu/TC_impact.html). For the northern Gulf Coast counties probabilities of a hurricane and major hurricane impact are in the upper 20ish percentile range and near 10% respectively. So in seasons with similar expected activity and steering patterns as this one there is roughly a 1 in 3 chance of a hurricane impact and a 1 in 10 chance of a major hurricane impact for any given county along the northern Florida Gulf Coast. See the previous link for county by county numbers. Other seasonal forecasts are in the same vein but that is more or less all you need to know.

As an aside, the local weather offices and National Hurricane Center are always great sources of info. If you're looking for some extra information that is very reliable year after year, Crown Weather Services is second to none. I'm a subscriber and have been for many years. A variety of subscriptions are available. They send out emails and have a great website with tons of info (not just about tropical weather). You can find them here: https://crownweather.com/.

Regarding the potential for early season activity, there have been some hints (okay, more than just hints) that we may see some activity in the western Caribbean as early as this coming Friday. The GFS (the US's main global weather model) and the GEFS (a multi-model ensemble of the GFS) has consistently been showing development in this area. The Canadian and UK ensembles have also been showing the potential for development here. The ECMWF (Euro) ensembles aren't as bullish and are indicating more of a chance of development in the Eastern Pacific. You may see some social media posts showing a hurricane in the Gulf sometime next week. While this isn't an impossibility it is not very likely this time of year for a number of reasons. What we see most often in the early season are highly sheared easterly weighted storms that are windy rainmakers. At this point it's too far out to know if, when, and where something may form. I just want you to have a heads up because of the stuff you're likely to see online. If it helps, the Global Tropical Hazards Outlook isn't showing any development through May 24th.

That's it for this first post of the season. It's a good idea to start getting a hurricane kit together (https://www.floridadisaster.org/planprepare/hurricane-supply-checklist/ or similar) and to think about what your evacuation plans may look like.

Have a good week, I'll send another update by the end of the week. For those that are interested, all of these are posted to my blog (https://www.deepsouthwx.com/) and you can also follow me on Twitter @DeepSouthWXUS.

Chris

Severe Weather Risk for Today Increased

May 6, 2022

I was not expecting a round of storms along the coast this morning! A line moving east from Louisiana was expected to fall apart overnight but that didn't happen. The storm prediction center has added an enhanced risk area (orange) for more or less the southeastern half of Alabama (if you fold the state from NW to SE) and eastern TN. The tornado risk has also been increased in the slight risk area. In eastern/southeastern AL there is a 10% chance of a tornado, 30% chance of damaging winds, and 15% chance of hail. The 30% wind risk also extends a bit into eastern TN. The slight risk area (yellow), which includes a 5% tornado chance, and 15% chance of damaging wind and hail covers most of the rest of the state of AL, the FL coast through the Big Bend, and the eastern half of TN.

Timing is mostly the same as yesterday (and when I say timing I mean timing of the worst weather) with severe weather possible from morning through the afternoon or evening for most areas, see graphics for your area.

Day 1 Outlook

Huntsville Area (what, no nice map?)

Birmingham Area

Mobile-Pensacola

Destin-Panama City and Parts East

Except for maybe eastern TN it looks like the weather will clear out by Saturday morning so the weekend should be pretty nice with cool evenings all the way to the coast for a few days.

Stay safe today and have a great weekend.

Chris

Severe Weather Possible Today and Tomorrow

May 5, 2022

Happy Cinco de Mayo! I actually thought we were done with the severe weather threat this season but it looks like at least one more round is possible today and tomorrow. The main threat will be tomorrow afternoon through evening with all modes possible (wind, hail, and an isolated tornado or two), albeit at a fairly low chance, from the coast up through NE AL and eastern TN. There will also be a little bit of a threat today and tonight for NW AL. I'm running late getting out the door for work so I'll let the graphics do the talking.

Day 1 (7 a.m. today through 7 a.m. tomorrow)

Day 2 (7 a.m. tomorrow through 7 a.m. Saturday)

Huntsville Area

Birmingham Area

Mobile-Pensacola

Destin-Panama City

I won't go into details but the forecast for our last event (April 15-17) did pretty well except for the 16th, there were few if any severe weather reports that day.

That's it for today, have a good end of the week and a great weekend.

Chris