Tropical Storm Arlene—40mph/998mb

[WxWatcher007]

The 2023 Atlantic hurricane season has arrived, and we have our first orange of the season in Invest 91L. 

Overnight we saw a little more organization, with pressure falls and persistent convection near a center of circulation. This led to the odds of development being raised this morning by the NHC. 

Satellite and radar still show that there are headwinds for tropical cyclone genesis, as westerly shear has convection lopsided on the eastern side of the system. It should be noted that it's June 1st lol, so most tropical this time of year is near the coast and often "slop". 

That said, recon is scheduled for today and tomorrow, the real window of development before the conditions become much more unfavorable. 

For those that are new to the tropical subforum--we use these threads to separate discussion for distinct areas of interests and named systems. 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Thu Jun 1 2023

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Northeastern Gulf of Mexico (AL91):
Showers and thunderstorms associated with an area of low pressure 
over the northeastern Gulf of Mexico have increased and become 
better organized during the overnight hours. Environmental 
conditions appear marginally favorable for additional development 
over the next day or so, and a short-lived tropical depression or 
storm could form over that time span as the system meanders over the 
northeastern Gulf of Mexico. However, by this weekend environmental 
conditions are forecast to become unfavorable for additional 
development as the system drifts southward, likely remaining 
offshore over the Gulf of Mexico. An Air Force Reserve Hurricane 
Hunter aircraft is scheduled to investigate the system later today, 
if necessary.

Regardless of development, locally heavy rainfall could occur over 
portions of the Florida Peninsula through this weekend. Additional 
information on the rainfall and flooding potential can be found in 
products issued by your local National Weather Service forecast 
office and Excessive Rainfall Outlooks issued by the Weather 
Prediction Center.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...50 percent.

Today marks the first day of the Atlantic hurricane season, which 
will run until November 30. The long-term averages for the number of 
named storms, hurricanes, and major hurricanes are 14, 7, and 3, 
respectively.

The list of names for 2023 is as follows:

Name         Pronunciation       Name         Pronunciation
--------------------------------------------------------------------
--
Arlene        ar-LEEN            Lee          lee 
Bret          bret               Margot       MAR-go
Cindy         SIN-dee            Nigel        NY-juhl     
Don           dahn               Ophelia      o-FEEL-ya  
Emily         EH-mih-lee         Philippe     fee-LEEP 
Franklin      FRANK-lin          Rina         REE-nuh
Gert          ger                Sean         shawn
Harold        HAIR-uld           Tammy        TAM-ee
Idalia        ee-DAL-ya          Vince        vinss
Jose          ho-Zay             Whitney      WHIT-nee
Katia         KAH-tya

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tropical cyclone formation during the next seven days.  The issuance 
times of this product are 2 AM, 8 AM, 2 PM, and 8 PM EDT.  After the 
change to standard time in November, the issuance times are 1 AM, 7 
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Forecaster Papin/Cangialosi/Brown

[Normandy]

This one looks like it might get classified

[Ed, snow and hurricane fan]

Early season development from a non-tropical origin resembles 1997 (4 storms) and 2015 (3 storms) where there were MJJ developments before a much below to below average MDR year.  July 97 the last of the 4 was Cat 1 Danny that made landfall in Plaquemines Parish.

[Boston Bulldog]

Up to 70%/70% at 2pm EDT

[WxWatcher007]

Posting text as well 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Thu Jun 1 2023

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

1. Northeastern Gulf of Mexico (AL91):
Recent satellite wind data, along with buoy and ship observations 
indicate the area of low pressure over the northeastern Gulf of 
Mexico has a broad but well-defined circulation with maximum 
sustained winds of about 35 mph. Shower and thunderstorm activity 
associated with the low is also showing signs of organization. 
Environmental conditions remain marginally favorable for additional 
development, and if these trends continue, a short-lived tropical 
depression or storm is likely to form as soon as this afternoon. The 
system is likely to meander over the northeastern Gulf of Mexico 
through tonight but begin a slow southward motion on Friday. By 
this weekend, environmental conditions are forecast to become 
unfavorable for additional development as the system continues 
moving southward, likely remaining offshore over the Gulf of Mexico. 
An Air Force Reserve Hurricane Hunter aircraft is scheduled to 
investigate the system later this afternoon. 

Regardless of development, locally heavy rainfall could occur over 
portions of the Florida Peninsula through this weekend. Additional 
information on the rainfall and flooding potential can be found in 
products issued by your local National Weather Service forecast 
office and Excessive Rainfall Outlooks issued by the Weather 
Prediction Center.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...70 percent.

Forecaster Papin/Cangialosi

[NavarreDon]

Recon enroute now. Curious to see what they find.

[WxWatcher007]

Recon descending into 91L now. 

[NorthHillsWx]

Recon has found plenty of 35-40 kt wind. Circulation looks somewhat broad but I’d guess this is our first named storm of the year (yes I know there was a sub tropical storm in January). 

[WxWatcher007]

3 minutes ago, NorthHillsWx said:

Recon has found plenty of 35-40 kt wind. Circulation looks somewhat broad but I’d guess this is our first named storm of the year (yes I know there was a sub tropical storm in January). 

Agree. Thought we’d see a more well-defined circulation but this is pretty close to a tropical cyclone if it’s not there already. 

[NavarreDon]

Kinda surprised with the data they didn’t go 40. Dr Knabb said it’s a coin flip & the forecasters decision. Not a big discrepancy though.

[Prospero]

Happy First Day of Hurricane Season!

Yesterday felt like a Tropical Storm here in Gulfport, Florida.

 

[Hotair]

The cone on this one seems rather unusual to me.  Do we get many storms in the gulf that transit North to South ? 

[shaggy]

30 minutes ago, Hotair said:

The cone on this one seems rather unusual to me.  Do we get many storms in the gulf that transit North to South ? 

Definitely not typical in June 

[Normandy]

The system is heavily sheared but has good vorticity and likely will keep generating strong convection in the eastern quad.  I think recon will eventually find the winds to upgrade it at some point me.  Nothing major but I see a low end TS out of this.  as mentioned before the motion is interesting and atypical for june.

[NorthHillsWx]

FL winds do not support an upgrade but pressure and SFMR winds would. Circulation has definitely wrapped up since yesterday as well. It’s a flip of the coin I guess as to whether to upgrade it. It is definitely sheared but that is a tight circulation with convection firing nearby enough to make it look like a low end TS

[GaWx]

No upgrade with 11AM EDT advisory even with a SLP drop from 1007 to 1002 mb since the last advisory. 1002 is unusually low for a TD. This is from the NHC discussion:

Convection has persisted throughout the morning, although the 
tropical cyclone remains highly asymmetric and poorly organized. 
The low-level center is located southwest of the large area of 
persistent deep convection. An Air Force Hurricane Hunter aircraft 
has found no evidence of intensification this morning, and the 
Dvorak satellite intensity estimate continues to support a steady 
current intensity of 30 kt for this advisory. 

The Hurricane Hunters will continue investigating the system for the 
next several hours, and a short-lived increase to tropical storm 
intensity cannot be ruled out. However, conditions are expected to 
become increasingly unfavorable for intensification later today and 
tonight.

[olafminesaw]

1 hour ago, GaWx said:

No upgrade with 11AM EDT advisory even with a SLP drop from 1007 to 1002 mb since the last advisory. 1002 is unusually low for a TD. This is from the NHC discussion:

Convection has persisted throughout the morning, although the 
tropical cyclone remains highly asymmetric and poorly organized. 
The low-level center is located southwest of the large area of 
persistent deep convection. An Air Force Hurricane Hunter aircraft 
has found no evidence of intensification this morning, and the 
Dvorak satellite intensity estimate continues to support a steady 
current intensity of 30 kt for this advisory. 

The Hurricane Hunters will continue investigating the system for the 
next several hours, and a short-lived increase to tropical storm 
intensity cannot be ruled out. However, conditions are expected to 
become increasingly unfavorable for intensification later today and 
tonight.

With pressure outside the circulation being unusually low, around 1008mb, there's not much of a gradient. 

[GaWx]

5 minutes ago, olafminesaw said:

With pressure outside the circulation being unusually low, around 1008mb, there's not much of a gradient. 

 Fair enough but I've seen TDs with even less gradient get upgraded.

[NorthHillsWx]

18 minutes ago, GaWx said:

 Fair enough but I've seen TDs with even less gradient get upgraded.

It’s definitely close but with minimal/no land impacts and FL winds below TS force I don’t disagree with NHC. Right on the cusp of a name though wouldn’t take much to get a 40mph storm at this point

[NorthHillsWx]

Just now, NorthHillsWx said:

It’s definitely close but with minimal/no land impacts and FL winds below TS force I don’t disagree with NHC. Right on the cusp of a name though wouldn’t take much to get a 40mph storm at this point

Before typing this I hadn’t looked at most recent recon. This is a storm. FL winds up and SFMR winds between 35-40 kts

[GaWx]

16 minutes ago, NorthHillsWx said:

Before typing this I hadn’t looked at most recent recon. This is a storm. FL winds up and SFMR winds between 35-40 kts

Thanks. It wouldn't surprise me if they do upgrade with those winds. But I think that the highest FL winds are ~40-60 miles N of the center. Am I looking at the data correctly? If so, would that matter in the decision about upgrading?

[GaWx]

Arlene it is!

https://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/021433.shtml

Data from the Air Force Hurricane Hunters indicate that the 
depression has strengthened into a tropical storm.  On the last leg 
of the current mission, the aircraft found maximum 925 
mb flight-level winds of around 50 kt and SFMR surface winds of 
around 35 kt.  Based on these data, Tropical Depression Two has 
been upgraded to Tropical Storm Arlene with estimated peak winds of 
35 kt.

[HillsdaleMIWeather]

Arlene is no more