Alpha sets all-time record

By: Dr. Jeff Masters , 10:43 PM GMT on October 22, 2005

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Ever since the formation of two major hurricanes in July made it clear that the Hurricane Season of 2005 was going to challenge 1933 as the busiest season ever, I've been expecting to see the words "Tropical Storm Alpha" emblazoned on a hurricane tracking chart. Well, we've got the record now. The formation of Tropical Storm Alpha, the 22nd storm of the season, now makes 2005 the busiest hurricane season of all time. Still, it looks really strange to see the words "Tropical Storm Alpha" on the hurricane tracking charts, and gives a surreal cast to Hurricane Season of 2005 as we approach the Halloween season.

In keeping with the season, we have two very scary storms to talk about. The eye of very dangerous Category 2 Hurricane Wilma is moving offshore the Yucatan mainland this evening, a little earlier than I expected. This makes it more likely Wilma will be a bit stronger at landfall in Florida Monday--perhaps a strong Category 2 with 105 mph winds. We are not good at making intensity forecasts, and Wilma could easily be a Category stronger--or weaker. The argument for a weaker hurricane goes like this: Wilma's inner eyewall has collapsed, leaving an outer eyewall with diameter 80 miles in place. When an inner eyewall collapses like that, it usually takes at least a day for the eyewall to reform, and by a day from now, Wilma will start experiencing increased wind shear which will weaken her down to a Category 1.

The argument for a stronger hurricane goes like this: Wilma still has a large, intact circulation, and is still a Category 2 hurricane. She will not follow the usual normals (since this is the Hurricane Season of 2005, after all), and will re-intensify quickly over the warm waters that nurtured her rise to Category 5 status this week. By late Sunday, she will be a Category 3 hurricane again, and large enough and fast moving enough that the shear affecting her will be unable to significantly weaken her. Wilma will make landfall as a major hurricane on Florida's west coast.

So, both scenarios are plausible, and Florida must be prepared for the arrival of a major hurricane on Monday. Landfall anywhere between Sarasota and the Keys is possible.

The remainder of my 1 pm post appears below, mostly unchanged.

The most extreme winds of the eyewall have now been battering Cozumel and the mainland Yucatan Peninsula for over 30 hours. Sustained winds of 100 - 140 mph affecting a built-up resort area like Cozumel/Cancun for so long must have done extreme damage. Wilma has weakened to a Category 2 hurricane with 100 mph winds. Still, the damage to Mexico will increase today as structures already weakened by 30 hours of relentless winds continue to receive another 12 hours of stress.

Conditions in Cancun
Wunderblogger LizinCancun reported yesterday on conditions in Cancun:

"We evacuated our home in Cancun yesterday and came 200 miles west to Merida. Our home sits about 100 feet away from the beach. The waves were crashing over our 6 foot tall sea wall yesterday before we left and destroyed the palapa that sits about 10 feet out in the water. We fully expect our home and all our belongings to be gone. We lost contact with all of our friends that stayed, cell and land lines are down of course as is power. We just talked with a friend that says the power is out, phones only working when the generators are running to pump out all the water. He said the hotel is blowing apart (not in the hotel zone) and all you can see when looking outside is a wall of water blowing sideways and pieces of things being shredded by the high winds, some huge."


Figure 1. Total rainfall for the week. Image generated by NASA's TRMM rainfall measuring satellite.

A deluge of rain
Rainfall amounts in Mexico from Wilma have been extreme. Isla Mujeres, just offshore from Cancun, has reported almost 35" of rain over the past 1 1/2 days, and at one point reported 4" of rain in one hour between 2 and 3 am EDT today. Rainfall amounts in Cuba have not been nearly so extreme--at least in the areas of western Cuba that are still reporting data. San Juan y Martinez measured 10.7 cm (4.2 inches) of rain the past 24 hours, and storm total rainfall amounts of up to 18 cm (7 inches) have been measured in Cuba's westernmost province. Grand Cayman received five inches, Jamaica's Kingston airport eight inches, and Belize four inches. The north coast of Honduras has had numerous locations receive ten inches of rain, with one unofficial report of 20 inches. Rainfall in Haiti reached 8 - 10 inches, and, triggered flash floods that killed 11 people.

How will Wilma affect Florida?
The latest 8 am EDT (12Z) model runs are in, and continue to agree on the basic scenario that Wilma will move offshore the Yucatan tonight as a weak Category 2 hurricane. On Sunday, the storm will move slowly north and then northeast as westerly winds from a strong trough of low pressure start affecting the storm. There is about an 18-hour window of opportunity for Wilma to re-intensify to a Category 3 hurricane on Sunday. By Sunday night, the Wilma will begin to accelerate, and wind shear will begin to weaken the storm. By Monday morning, Wilma will cross the west coast of Florida between Fort Myers and the Keys as a Category 1, 2, or 3 hurricane. My best guess is that Wilma will be a 110-mph Category 2 hurricane hitting near Marco. Storm surges tend to be worse with large and faster moving hurricanes, so I would expect a storm surge characteristic of a Category 3 hurricane, 10 to 16 feet, in and south of Marco, causing very heavy damage in that city. Fortunately, the area south of Marco is primarily uninhabited--the Everglades swamp. However, if Wilma comes ashore north of Naples--or further south near the Keys--storm surge flood damage in those areas could easily reach billions of dollars. Storm surge flooding should be only 2 - 4 feet on the east coast of Florida, where wind damage is the primary threat.


Figure 2. Storm surge map for southwest Florida.

Wilma's winds and rain
Wilma will be moving too fast to dump more than 5 - 10 inches of rain. The rain will be concentrated on the north side of the hurricane, since there will be a cold front there that will trigger more condensation. Areas to the north of the eye's passage will see winds a full Category--25 to 30 mph--lower than those on the south. This is because the storm's high rate of forward motion, near 25 - 30 mph, will add to the windspeeds seen on the south side of the Wilma's counterclockwise rotation, and subtract on the north side. Since the storm will be moving so fast, the duration of hurricane force winds will be just a few hours.

After Florida, then what?
After crossing Florida, Wilma should bring tropical storm force winds to the northern Bahama Islands, but not hurricane force winds. Wilma should pass close enough to North Carolina's Outer Banks to bring 40 mph winds there. Wilma is not expected to bring high winds to New England, but could bring 50 mph winds to Nova Scotia five days from now.

Alpha
Alpha has formed 200 miles southeast of Hispanolia. Long range radar from San Juan, Puerto Rico shows some increasing spiral banding and echo intensity, and satellite imagery shows a good outflow channel developing to the southeast. Wind shear of about 10 knots is eroding the northwest portion of the storm.

Given the storm's expected track over Haiti, the 8 - 12 inches of rain expected may cause heavy loss of life in that country due to the inability of the deforested hillsides to handle flood waters. The Dominican Republic, which still has 70% of its forest cover, should fare relatively well.

I'll be back in the morning with the latest.

Jeff Masters

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163. Hecker
6:35 PM GMT on October 23, 2005
La Bajada radar shows Wilma's eye still large and possibly open to the NW. Forward speed is picking up, I think.
Member Since: June 29, 2005 Posts: 24 Comments: 308
162. GoldenGate
5:58 PM GMT on October 23, 2005
Hey Nightblooming....I hear you...I talked to neighbors who are staying because of how hard it was to get back in after Charley. I'll ride out the storm with you...as long as I have the internet. I'm wondering how long I can go without the internet before I start to go through withdrawal. It could get ugly.
161. globalize
4:23 PM GMT on October 23, 2005
Very early this morning it looked as if the pinhole eye feature was forming again. Wouldn't that mean the wind field would probably contract?
Member Since: August 30, 2005 Posts: 0 Comments: 1150
160. MisterJimster
4:19 PM GMT on October 23, 2005
WinterParkgirl, sorry, I meant lot's of rain and some wind.
159. olefosse
4:19 PM GMT on October 23, 2005
Inverse EWRC?? Inwards-out? Seems to me like that is what she is trying to do.
Link
Wouldn't such a thing be quite unheard of? Any comments on this?
158. keeywester
4:18 PM GMT on October 23, 2005
I think we are starting to see some intensification unfortunately. We may have a well defined eye 4 or 5 hours from now.
157. MisterJimster
4:16 PM GMT on October 23, 2005
WinterParkgirl, I live in St. Pete and though I think you will get lot's of rain and some rain it doesn't look like the eye will be very close. If you were here last year you probably experienced Francis and Jeanne.
156. eriewa
4:16 PM GMT on October 23, 2005
Hello everyone! Ijust wanted to know if anybody has an idea on how Willma may affect Hendry Co. I have 2 daughters that live there. And what about the lake will the water be pushed to the east bacause the storm is entering from the west last year when the storms came from the east they was worried about the dike holding. Could that be a problem with this storm? thanks
155. globalize
4:16 PM GMT on October 23, 2005
Dacula- see the forming eyewall. It is amazing how the storm is maintaining symmetry in the face of the dry air from the west.
Member Since: August 30, 2005 Posts: 0 Comments: 1150
154. Dacula
4:14 PM GMT on October 23, 2005
i am seeing that too, keeywester!!!
153. keeywester
4:12 PM GMT on October 23, 2005
It looks like the north coast of Cuba might take a pretty good hit this afternoon from the southern part of the eyewall.

I dont like the way the strong bands are starting to wrap in closer to the center.
152. Dacula
4:11 PM GMT on October 23, 2005
Does anyone see an eyewall trying to form??
151. globalize
4:07 PM GMT on October 23, 2005
anglosaxon- who knows, with most all physical limits concerning meteorology out the door. But given the November cooler waters, probably not much more than the moisture/convection of one system being absorbed into the other.
Member Since: August 30, 2005 Posts: 0 Comments: 1150
150. ansaman
4:06 PM GMT on October 23, 2005
What is with the lack of timely updates
to Jeff Master's Blog?

For such an important storm, there sure
isn't a lot of commentary.
149. keeywester
4:06 PM GMT on October 23, 2005
After a beautiful morning of partly cloudy skies and light breezes......it just got cloudy here real fast (12 noon) It looks like the first outer band is about 35 miles away.

I know all the models take this thing in further north but the current satalite loops are making me nervous...if it keeps on it's current path it looks like it will come in near Everglades city.....and Key West will be a little too close for comfort.
148. ansaman
4:05 PM GMT on October 23, 2005
What is with the lack of timely updates
to Jeff Master's Blog?

For such an important storm, there sure
isn't a lot of commentary.
147. sts100launch
4:01 PM GMT on October 23, 2005
Hi all, Mobile here and after reading some posts about how this house has stood storms for 40 yrs or 50 yrs so "I'm staying" let me remind all about Mississippi gulf coast. Sen Trent Lott's house 150 yrs GONE... Confederate President Jeff Davis's home sever damage. Numerous homes of 100 to 200 yrs old.....nothing but foundations.... I heard lots of people say "Oh my house made it through Camile" well they didn't make it through Katrina. I know Wilma is not a strong but I don't think based on the 2005 season that "It made it through this storm or that storm" is a sound reason not to leave especially if under an evacuation order. Just my thoughts... Good luck to all in FL and God Bless.
Member Since: September 28, 2005 Posts: 0 Comments: 6
146. anglosaxon
3:50 PM GMT on October 23, 2005
What does it mean that Alpha & Wilma appear to be on a collision course according to forecasts?
145. Jeremey
3:47 PM GMT on October 23, 2005
Well, I'm going back outside to pick up some stuff, you never know how much stuff you have outside till you have to move it all inside!
144. Jeremey
3:44 PM GMT on October 23, 2005
Hey winter, try www.skeetobiteweather.com too, they have some good model images on there too.
143. ricstevenson
3:39 PM GMT on October 23, 2005
Jeremey. thank you!!! i will contact you via your login here.
142. nightbloomingjasmine
3:39 PM GMT on October 23, 2005
Hi GG Change of plans we're staying put. Don't want to fight traffic trying to get back home
141. mybahamas
3:37 PM GMT on October 23, 2005
Hiya :)
Here's the link to the simple music track to HillboroughBay's Wilma poem :)

Link

140. Jeremey
3:32 PM GMT on October 23, 2005
Hey Ric, I just rewinded my DVR and recorded it, I live in Punta Gorda so if the weather channel doesn't give you a copy of it, I can get it to you. Or if I feel productive, I can record it onto the computer.
139. Skyepony (Mod)
3:31 PM GMT on October 23, 2005
Link sorry
Member Since: August 10, 2005 Posts: 161 Comments: 37300
138. Skyepony (Mod)
3:31 PM GMT on October 23, 2005
models, scroll right hit forward
Member Since: August 10, 2005 Posts: 161 Comments: 37300
137. WinterParkgirl
3:29 PM GMT on October 23, 2005
Hello, Newbie here, first post.

For those who are saying the models are moving south, can you tell me what you're looking at?

If it's on the web, can you post sites because this is the first hurricane I am really following this closely, and there's nothing on the few TV stations I get. The fact that they seem to be guessing is scary to me.
136. seflagamma
3:28 PM GMT on October 23, 2005
Good job Ric, wish I had seen it...Gamma
Member Since: August 29, 2005 Posts: 297 Comments: 40881
135. GoldenGate
3:26 PM GMT on October 23, 2005
Bizarre sense of calm here. It is really sunny here. We are all prepared, everything is done, so.....my dogs and I are sunbathing and swimming in the pool. It is surreal.
134. ricstevenson
3:21 PM GMT on October 23, 2005
eh, i've been on tv before and published in the paper. it's no big deal to anyone but me... and dad i guess. i called dad right after and he picked up the phone and said "you need to shave". :)
133. sngalla
3:15 PM GMT on October 23, 2005
Wow. A celebrity is among us. (Bows down) Lol.
Member Since: February 18, 2003 Posts: 57 Comments: 5363
132. ricstevenson
3:13 PM GMT on October 23, 2005
giggle. i just emailed the weather channel and asked for a copy of it... tape, dvd, computer file... whatever.
131. CaneBob
3:11 PM GMT on October 23, 2005
Sorm is headed a little East of NE not exactly ENE. I am afraid the people of SE Florida are taking Wilma a little too lightly. All the models are shifting South now and Dade and Broward Counties will possibly see the worst of the storm on the East Coast. Naples and Marco Island seem to habe the bullseye on the West Coast. The only blessing seems to be that the storm will be moving at a rapid pace and out of here fairly quickly. Good luck to all.
Member Since: October 22, 2005 Posts: 0 Comments: 85
130. FrancesJeanne
3:10 PM GMT on October 23, 2005
You know you spend too much time lurking around on here when you hear someone's name on tv and you can visualize the spelling of it right down to it being all one word lol
Member Since: July 27, 2005 Posts: 0 Comments: 27
129. ricstevenson
3:06 PM GMT on October 23, 2005
yeah, i went to the beach cuz i saw jeff morrow on and just thought i'd see it in person... and they asked to interview me! that was cool. i called my dad in phoenix right ahead of it so he got to see me. i just wish i had a tape of it
128. turtlehurricane
3:06 PM GMT on October 23, 2005
i hav updated my blog
Member Since: July 22, 2005 Posts: 227 Comments: 469
127. MisterJimster
3:05 PM GMT on October 23, 2005
Man, I can't believe how lucky we have been here in the Tampa Bay area for so long.
126. FrancesJeanne
3:04 PM GMT on October 23, 2005
Ric, that is so bizarre ... they said Ric Stevenson and I was thinking "where have I seen that name before? Nah... couldn't be!"
Member Since: July 27, 2005 Posts: 0 Comments: 27
125. mybahamas
3:03 PM GMT on October 23, 2005
Thanks Jimster :)
I just noticed that all the computer models shifted more south just now :(
124. MisterJimster
3:01 PM GMT on October 23, 2005
Mybahamas, hopefully she will be a weak cat 1 or less in your area. I doubt you have much to worry about with Alpha either.
123. ricstevenson
3:00 PM GMT on October 23, 2005
did anyone see me on tv about 20 minutes ago?
122. mybahamas
2:58 PM GMT on October 23, 2005
Excerpt from Advisory

At 10 am CDT...1500z...the center of Hurricane Wilma was located
near latitude 22.7 north... longitude 85.8 west or about 285
miles... 460 km... west-southwest of Key West Florida... or about
340 miles... 545 km... southwest of the southwestern coast of the
Florida Peninsula.

Wilma is moving toward the northeast near 8 mph...13 km/hr. A
gradual increase in forward speed is expected today and tonight.

Maximum sustained winds are near 100 mph...160 km/hr...with higher
gusts. Wilma is a category two hurricane on the Saffir-Simpson
scale. Some strengthening is possible today or tonight.

Hurricane force winds extend outward up to 70 miles...110 km...
from the center...and tropical storm force winds extend outward up
to 200 miles...325 km.

Estimated minimum central pressure is 961 mb...28.38 inches.
Storm surge flooding of 8 to 13 ft above normal tide levels is
possible along the southwest Florida coast near and to the
south of where the center of Wilma makes landfall. Storm surge
flooding of 5 to 8 ft above normal is possible in the Florida Keys
and Florida Bay...as well as in Lake Okeechobee. Storm surge
flooding of 2 to 4 feet is possible along the extreme southeastern
coast of Florida. Storm surge flooding along the Yucatan Peninsula
and the nearby islands should gradually subside as Wilma moves
away.

Wilma is expected to produce additional rainfall accumulations of 10
to 15 inches through Sunday across portions of western Cuba and 2 to
4 inches across the northeastern Yucatan Peninsula... with isolated
maximum storm total amounts approaching 50 inches. Rainfall across
southern Florida including the Keys through Tuesday is expected to
be 4 to 8 inches... with isolated maximum amounts of 12 inches
possible.
121. MisterJimster
2:56 PM GMT on October 23, 2005
Hurricane Wilma Advisory Number 33
120. hswiseman
2:52 PM GMT on October 23, 2005
As forward velocity of Wilma increases it should catch up with some of the convection it is creating (currently blowing off into the lljet.). It should hold its own or intensify somewhat before landfall. Cat3 is probably a stretch, but forward acceleration will add some ummph to west coast areas that get the SW eyewall (such as it is) on landfall
Member Since: August 29, 2005 Posts: 0 Comments: 44
119. mybahamas
2:48 PM GMT on October 23, 2005
Hiya Master Jimster :)
I am in Nassau and we are under a hurricane warning. Fortunately, my supply of plywood is on the way to my house. :)
Unfortunately, I think that my southernmost window might be too high for me to reach, even with my 22-foot ladder :( I have a pondview property with a balcony and haven't received my rolldowns for that side yet :(
However, I already have two shuttered rooms in my house that could be used as "safe" rooms.
The best to all in this hurricane season :)
118. MisterJimster
2:43 PM GMT on October 23, 2005
Looks like the Tampa St. Pete. area is going to escape the worst. Being on the north side of the expected landfall will decrease the wind velocity by the value of the forward motion of the storm. Probably will see some 50-60 winds and loads of rain.
117. MisterJimster
2:39 PM GMT on October 23, 2005
Mybahamas, not sure where you are exactly over there. Are you under the new hurricane warning? Some of the Bahamas is under a hurricane warning and some under a tropical storm warning do to Alpha.
116. wxfan
2:37 PM GMT on October 23, 2005
Both eyewalls seem to be collapsing and convection on the North side of the storm is being blown away at 30+ mph. The storm has to be moving 12-18mph, now. She may be a CAT 1 at next advisory.
Member Since: August 23, 2005 Posts: 0 Comments: 18
115. FLSpud
2:29 PM GMT on October 23, 2005
Hey ClydeFrog ~ I work in Gainesville, but live in Citrus County, a couple of counties down. If you are expecting gusts of 30-40 mph, what do you think Citrus will get? We are about 70 miles south.

Thanks in advance!
114. tidalwavedave
2:26 PM GMT on October 23, 2005
Hey folks,
I'm on Big Pine Key and I am trying to figure out which direction the surge is supposed to approach from. The National Data Buoy Center page (marine forecast) has the winds increasing from the SW. So why is everyone reporting that the surge will come into the bay? The south wind (in the lower Keys) should force the surge into the Gulf. Any wisdom out there?

Take care everyone.

twd
113. BigJohnTheHustler
2:25 PM GMT on October 23, 2005
It is fun to watch and be part of the scramble to put up pre-fab aluminum shutters... I think every place should be required to have those F'in accordian shutters so you just pull em shut and your done.... you can almost even do 'em during a storm, you know...

1 time for all the West Palm Beach folks doing the same thing as me!

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.