Subtropical Storm Beryl forms
The second named storm of this unusually fast-starting 2012 Atlantic hurricane season is here. Subtropical Storm Beryl formed Friday night, a few hundred miles east of the South Carolina coast, from an area of disturbed weather that had moved from the Western Caribbean northeastward. Beryl's formation marks the first time since the hurricane season of 1908 that two Atlantic named storms have formed so early in the year. The only other year with two storms so early in the year was 1887. Records of tropical cyclones in the Atlantic extend back to 1851.
Figure 1. Morning satellite image of Beryl.
The clockwise flow of air around an extremely intense ridge of high pressure that is bringing record heat to the Midwest this weekend is currently driving Beryl to the southwest, and this motion is likely continue until Beryl is very close to the Georgia/Northern Florida coast on Sunday night. As I explain in my Subtropical Storm Tutorial, a subtropical storm typically has a large, cloud free center of circulation, with very heavy thunderstorm activity in a band removed at least 100 miles from the center. The difference between a subtropical storm and a tropical storm is not that important as far as the winds they can generate, but tropical storms generate more rain. A key difference between tropical and subtropical storms is that tropical systems have the potential to quickly grow into hurricanes, while subtropical storms do not. Thus, we need not be concerned about Beryl intensifying to hurricane strength while it is still subtropical. If the storm manages to build a large amount of heavy thunderstorms near its center, these thunderstorms should be able to add enough heat and moisture to the atmosphere to turn Beryl into a tropical storm. This process will be aided as Beryl passes over the warmest waters of the Gulf Stream Saturday night and Sunday morning. But as Beryl makes its likely transition to a tropical storm on Sunday afternoon and evening as it approaches the coast, the storm will move off of the warmest Gulf Stream waters into waters that are cooler (25°, 77°F), and with with lower total heat content. This will limit the storm's potential to strengthen. The 11 am Saturday wind probability advisory from NHC gave Beryl just an 8% chance of becoming a hurricane. There is a lot of dry air surrounding Beryl, thanks to an upper-level low pressure system aloft, and this will keep rainfall amounts much lower that what we would expect if Beryl was a tropical storm. Thus, flooding due to heavy rains is probably not a huge concern with this storm, particularly since the Southeast U.S. coast is under moderate to extreme drought. The 2 - 4 inches of rain expected from Beryl will not be enough to bust the drought, since the Southeast U.S. is generally suffering a rainfall deficit of 8 - 12 inches (since October 1.) Heavy rains from Beryl are not likely to begin affecting coastal South Carolina, Georgia, and Northern Florida until Sunday.
Figure 2. Moderate to exceptional drought is currently gripping the Southeast U.S.; Beryl's rains would be welcome. Image credit: U.S. Department of Agriculture.
Bud hits Mexico and dissipates
Hurricane Bud hit Mexico as a tropical depression early this morning, and has now dissipated, thanks to dry air, wind shear, and interaction with Mexico's mountainous terrain. As Bud approached Mexico on Friday, it brought tropical storm-force winds and heavy rains to the coast. Winds at Manzanillo peaked at 41 mph, with a gust to 55 mph, Friday afternoon. Thursday night at 11 pm EDT, Bud peaked at Category 3 status, with 115 mph winds, becoming the earliest Category 3 hurricane on record so early in the year in the Eastern Pacific. There are no reports of deaths or damage from Bud so far, and with only another inch or so of rain expected from the storm, Mexico appears to have escaped serious damage.
Figure 3. True-color satellite image of Hurricane Bud taken by NASA's Terra satellite at 1:15 pm EDT May 25, 2012. At the time, Bud was a Category 1 hurricane with 85 mph winds. Image credit: NASA.
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 — Blog Index
1. The national hurricane center got some splainin to do
2.Wonder how the national hurricane center likes their crow cooked?
They marked that as questionable.
on the tropical atlantic recon site it is not marked as questionable
nevermind that one is marked, but one with stronger 30 second surface winds is not
yeah, I think it's conservative to say just a 50mph Storm. also I think the forecast track could be a little more south.
Strange. The temperature, dewpoint, rainrate, and surface winds are all marked questionable on GREarth.
No you were right, that ob was marked, but there was a reading with 50mph 30 sec average that was not marked
Coordinates: 31.9N 75.9W
Acft. Static Air Press: 963.3 mb (~ 28.45 inHg)
Acft. Geopotential Hgt: 404 meters (~ 1,325 feet)
Extrap. Sfc. Press: -
D-value: -
Flt. Lvl. Wind (30s): From 121° at 54 knots (From the ESE at ~ 62.1 mph)
Air Temp: 16.0°C* (~ 60.8°F*)
Dew Pt: -*
Peak (10s) Flt. Lvl. Wind: 55 knots (~ 63.2 mph)
SFMR Peak (10s) Sfc. Wind: 43 knots (~ 49.4 mph)
SFMR Rain Rate: 12 mm/hr (~ 0.47 in/hr)
(*) Denotes suspect data
Roger and copy dat Houston.
Doesn't matter the month when I'm seeing the conditions that Beryl has in front of her. They are not ideal, no, but they are favorable enough for a stronger storm.
I'd have to agree with you. This is probably tropical now.
Tonight may show that trend continuing..
The Log is lit, the flue is open, and warmer SST's if she Keeps to track..
And along with it, the ACE rating will start to go up too.
Storm Relative 1km Geostationary Visible Imagery Loop
ZOOM image by clicking on it
It'll probably eventually have an eye feature like Sean. Most subtropical storms do.
There is hope yet!!
Looks like it is becoming tropical, I am right?
The fact is, idc what time of year we are in, if the atmosphere does not favor development in July or August or any other month, then that wave in May still wouldnt develop and that weak TC in May may just stay as a weak TC.
Perhaps, key word being "feature"...
If the Trend continues as it seems, expect the winds to reflect it downstream tonight.
A bit of dry air near the CoC but there's plenty of moister air to her southeast now.
I agree. I'll eat it with you too if we're wrong.
Make that me, too. LOL.
Tomorrow at 12Z and 22Z.
That is absolutely correct. A system has to be fully tropical in nature (no contributing baroclinic features directly associated with its circulation) in order for it to be classified as a hurricane-even if it were to contain a MSW of 74 mph or greater. It is very rare for a Subtropical storm to achieve such wind speeds, but it has happened before.
Classifying whether TS or STS apparently is truly subject to one's interpretation, but I largely look at upper air analysis of the environment the sfc low is under and being dominated by to the greatest extent -- currently Beryl remains co-located right under the large, expansive ULL trof, not the upper ridge and is a classic STS.. In fact the 12Z GFS analysis forecast - should it's depiction verify - of 300 / 250 / 200 mb heights would indicate Beryl primarily remaining under that troughing influence thru at least another 36 hrs, perhaps right up to landfall... However by that time or sooner, a case could be made that it's displaying more warm core characteristics higher into the upper levels and might be located partially - or near equally - under both the upper trof (which may or not be more to the east) and ridge to the NW / N... That's when it really gets subjective!
For that matter, I viewed Alberto as being more worthy of a subtropical designation as well at the time the NHC declared it as tropical... So be it, lol...
Happy swirl watching! Very doubtful given the abundance of dry air nearby that we'll see anything approaching Lee-type rainfall rates out of Beryl, but beach-goers should definitely respect those nasty swells and rip currents... ;)
G'day!
I Agree 100%, This morning it had no convection around the center. Now look at it...
You would be a ridiculously wealthy individual.
Viewing: 551 - 601
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 — Blog Index