Rare February tropical disturbance drenching the Florida Keys

By: Dr. Jeff Masters , 1:51 PM GMT on February 06, 2012

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Our calendars may say it's February, but Mother Nature's calendar says it's more like May in the waters of South Florida, where the year's first significant tropical disturbance is drenching the Keys. The disturbance, designated Invest 90L by NHC late Sunday morning, has dumped 1 - 3 inches of rain over much of the Florida Keys this morning, with Key West receiving 4.34" of rain on Sunday, a record for the date. The storm was close to developing a surface circulation last night, thanks to wind shear values to fell to 20 - 25 knots, and NHC gave 90L a 30% chance of developing into a subtropical depression in a special Tropical Weather Outlook issued last night. However, wind shear has increased to a prohibitive 30 - 40 knots this morning, and 90L is looking much less organized. In their 7 am EST outlook this morning, NHC gave 90L a 0% chance of developing. The system will continue to grow less organized today as it moves over Nassau in the Bahamas and heads out to sea.


Figure 1. Radar-estimated rainfall from Invest 90L.

What's going on?
Obviously, strong tropical disturbances capable of developing into named storms are very rare in February, and I've never seen one in my 30 years as a meteorologist. However, ocean temperatures are warm enough year-round to support a tropical storm in the waters of the Western Caribbean. Water temperatures today in the region were 26 - 26.5°C (79 - 80°F), which is near average for this time of year. If an unusual configuration of the jet stream allows wind shear to drop below about 25 knots in the Western Caribbean, there is the opportunity for a rare off-season tropical storm to form in February. I discussed in an appearance on NPR's All Things Considered on Friday just how unusual the atmospheric flow patterns have been this winter, and today's rare tropical disturbance over South Florida is symptomatic of how whacked-out our 2012 atmosphere has been. In isolation, the strange winter weather of 2011 - 2012 could be a natural rare occurrence, but there have been way too many strange atmospheric events in the past two years for them all to be simply an unusually long run of natural extremes. Something is definitely up with the weather, and it is clear to me that over the past two years, the climate has shifted to a new state capable of delivering rare and unprecedented weather events. Human emissions of heat-trapping gases like carbon dioxide are the most likely cause of such a shift in the climate, as I discussed in my post last week, Where is the climate headed?

A historical precedent: the 1952 Groundhog's Day tropical storm
There is a historical precedent for a tropical storm this time of year--the 1952 Groundhog's Day tropical storm that hit Southwest Florida. According to Wikipedia,

The 1952 Groundhog Day Storm was the only Atlantic tropical cyclone on record in the month of February. First observed in the western Caribbean Sea on February 2, it moved rapidly throughout its duration and struck southwestern Florida within 24 hours of forming. In the state, the winds damaged some crops and power lines, but no serious damage was reported.

Meteorologist Andrew Hagen performed a re-analysis of all the tropical storms between 1944 - 1953 for his Ph.D. thesis, and looked in detail at the 1952 Groundhog Day's storm. He noted that it didn't look like a classic tropical storm, but it didn't look like an extratropical storm, either, and should stay in the database as the first named storm of 1952. In the old teletype files for February 1952, he found a February 2 message from the Cuban Weather Service that expressed some concern about possible tropical development between Cuba and Florida. NHC responded: "TROPICAL STORMS DO NOT FORM IN FEBRUARY."


Figure 2. February 2, 1952 teletype message from the Hurricane Center to the Cuban Weather Service, explaining that there couldn't possibly be a tropical storm in February. Image credit: Andrew Hagen.

Jeff Masters

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183. RTSplayer
2:01 AM GMT on February 07, 2012
Quoting chimera245:


Consider that a slope of 1/2 would imply an intercept at (2,3) (y = (0.5 * 2) + 2), the next intercept with a slope > 0.5 would be (1,3). Rearranging to m = (y - 2) / x gives:

m = (3 - 2) / 1

therefore max value of a is 1.


Ok, he wants the line to never pass through a lattice point between 0 < X < 100.

If m is rational and between 100 and 1/100, then the line will always pass through a lattice point, eventually.
Member Since: January 25, 2012 Posts: 33 Comments: 1520
182. hurricanehunter27
2:01 AM GMT on February 07, 2012
Quoting chimera245:


Consider that a slope of 1/2 would imply an intercept at (2,3) (y = (0.5 * 2) 2), the next intercept with a slope > 0.5 would be (1,3). Rearranging to m = (y - 2) / x gives:

m = (3 - 2) / 1

therefore max value of a is 1.
Already see a flaw in your math "m" has to be more than 50 and "a" has to be more than "m". Btw by that I mean like 51/100.
Member Since: July 22, 2010 Posts: 1 Comments: 3851
181. TheoJesse
2:00 AM GMT on February 07, 2012
#173 Nea.
Is there any explanations of what the colors represent?
Jesse
Member Since: September 27, 2008 Posts: 0 Comments: 304
180. hurricanehunter27
1:57 AM GMT on February 07, 2012
Quoting RTSplayer:


I have't done formal math in a while, but I don't think it has a maximum value, hence infinity.

m could be any irrational number and it would fulfill your criteria, because y would never be an integer since 0
"a" seems to be irrelevant, except to say that there must be "something" larger than m.

Since I see no irrational value of m that can't exist, then I suppose a should be infinity.


And then you can argue over whether one infinity is larger than another via the squeeze rule, etc.

Of course, I could be wrong. Like I said, it's been a while since I did formal math.
A)
No there is a def answer.
BTW these are fractions

51/101
50/99
51/100
52/101
13/25
Member Since: July 22, 2010 Posts: 1 Comments: 3851
179. j2008
1:56 AM GMT on February 07, 2012
Quoting KEEPEROFTHEGATE:


SOMETHING COMING
If it keeps this up we may just get Alberto this month......looks like we have 91L on the way. JMO
Member Since: December 19, 2008 Posts: 1 Comments: 224
178. presslord
1:55 AM GMT on February 07, 2012
Quoting chimera245:


Consider that a slope of 1/2 would imply an intercept at (2,3) (y = (0.5 * 2) + 2), the next intercept with a slope > 0.5 would be (1,3). Rearranging to m = (y - 2) / x gives:

m = (3 - 2) / 1

therefore max value of a is 1.


See?!?!?! This right here is what makes this blog so great!!! I have no idea if the answer is correct...because I have no idea what the question is asking...but ya just gotta love the spirit...
Member Since: August 13, 2007 Posts: 0 Comments: 10492
177. RTSplayer
1:55 AM GMT on February 07, 2012
Quoting hurricanehunter27:
A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx + 2 passes through no lattice point with 0 < x < (or equal to 100) for all m such that 1/2< m < a .
What is the maximum possible value of a?


Sry had to re-type that.


I have't done formal math in a while, but I don't think it has a maximum value, hence infinity.

m could be any irrational number and it would fulfill your criteria, because y would never be an integer since 0
"a" seems to be irrelevant, except to say that there must be "something" larger than m.

Since I see no irrational value of m that can't exist, then I suppose a should be infinity.


And then you can argue over whether one infinity is larger than another via the squeeze rule, etc.

Of course, I could be wrong. Like I said, it's been a while since I did formal math.
Member Since: January 25, 2012 Posts: 33 Comments: 1520
176. chimera245
1:53 AM GMT on February 07, 2012
Quoting hurricanehunter27:
A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx 2 passes through no lattice point with 0 < x < (or equal to 100) for all m such that 1/2< m < a .
What is the maximum possible value of a?


Sry had to re-type that.


EDIT: Note I changed this - after reading your question more carefully.

Aha. Starting with the slope at 0.5, you get intercepts at (2,3), (4,4), (6,5), generally up to ((n-2)*2,n).

Given that your limit of x (n-2)*2 is 100, then the largest one of these intercepts is where n = 52, i.e (100,52).

Moving m upwards moves the x value to the left, so our next intercept point would be (99,52) - this is the limit for m. Back substituting this point using:

m = (y - 2) / x

Gives me

m = (52 - 2) / 99

m = 0.5050...

Or am I missing something?
Member Since: January 13, 2010 Posts: 0 Comments: 32
175. sunlinepr
1:50 AM GMT on February 07, 2012
Member Since: August 2, 2010 Posts: 21 Comments: 9882
174. hurricanehunter27
1:42 AM GMT on February 07, 2012
A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx + 2 passes through no lattice point with 0 < x < (or equal to 100) for all m such that 1/2< m < a .
What is the maximum possible value of a?


Sry had to re-type that.
Member Since: July 22, 2010 Posts: 1 Comments: 3851
173. Neapolitan
1:42 AM GMT on February 07, 2012
From Uni Bremen, here are same-date images of ice coverage in the Barentsz and Kara Seas that show something pretty startling going on.

As Neven says over on his Arctic Sea Ice Blog: "The Sun is barely rising over the horizon right now and remains visible for only a couple of hours. But this will soon change and it won't be long before there is enough light for us to start gazing at the MODIS satellite images. Whether the sea ice will retreat even more in the meantime or whether we will see a late freeze-up in the Barentsz and Kara Seas, remains to be seen. But as things currently stand, the Atlantic side of the Arctic looks spectacular. Spectacular and ominous."

Click for larger image:

Uh-oh
Member Since: November 8, 2009 Posts: 4 Comments: 13743
172. WeatherNerdPR
1:39 AM GMT on February 07, 2012
Quoting hurricanehunter27:
All right wunderground. I need to test your math skills with a math probleme I cant figure out for the life of me. I turn to you as a last resort none of my mates know how to do it either.

A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx + 2 passes through no lattice point with 0 < x £ 100 for all m such that
1
2
< m < a .
What is the maximum possible value of a?

Funny, we just started taking something similar to that in class this semester. But, that problem is a little too much for me. Not to mention my books are in Spanish, so some of your wording confuses me.
Member Since: July 7, 2010 Posts: 0 Comments: 5725
171. SPLbeater
1:31 AM GMT on February 07, 2012
Quoting hurricanehunter27:
All right wunderground. I need to test your math skills with a math probleme I cant figure out for the life of me. I turn to you as a last resort none of my mates know how to do it either.

A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx + 2 passes through no lattice point with 0 < x £ 100 for all m such that
1
2
< m < a .
What is the maximum possible value of a?


i aint even at that level yet..and what i got i hate lol. sorry sport :/
Member Since: August 4, 2011 Posts: 46 Comments: 4488
170. KEEPEROFTHEGATE (Mod)
1:31 AM GMT on February 07, 2012
Quoting presslord:


Of 'a' what?!?!?!?!

a pack of smokes
a glass of beer
Member Since: July 15, 2006 Posts: 176 Comments: 55665
169. presslord
1:29 AM GMT on February 07, 2012
Quoting hurricanehunter27:
All right wunderground. I need to test your math skills with a math probleme I cant figure out for the life of me. I turn to you as a last resort none of my mates know how to do it either.

A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx + 2 passes through no lattice point with 0 < x £ 100 for all m such that
1
2
< m < a .
What is the maximum possible value of a?


Of 'a' what?!?!?!?!
Member Since: August 13, 2007 Posts: 0 Comments: 10492
168. hurricanehunter27
1:24 AM GMT on February 07, 2012
A lattice point in an xy-coordinate systems is any point (x,y) where x and y are both integers. The
graph of y = mx 2 passes through no lattice point with 0 < x < (or equal to 100) for all m such that 1/2< m < a .
What is the maximum possible value of a?


Sry had to re-type that.
Member Since: July 22, 2010 Posts: 1 Comments: 3851
167. RTSplayer
1:22 AM GMT on February 07, 2012
165:

Maybe that's the thing the GFS says will be in the Gulf on the 10th and 11th?

Weird stuff happening here. Very weird indeed.
Member Since: January 25, 2012 Posts: 33 Comments: 1520
166. Patrap
1:21 AM GMT on February 07, 2012
Gulf Of Mexico - False Color RGB Loop


..click Image for Loop

ZOOM is available

Member Since: July 3, 2005 Posts: 427 Comments: 129444
165. KEEPEROFTHEGATE (Mod)
1:19 AM GMT on February 07, 2012


SOMETHING COMING
Member Since: July 15, 2006 Posts: 176 Comments: 55665
164. SPLbeater
1:08 AM GMT on February 07, 2012
Im bored. And i am NOT fooling with that uncleverbot.
Member Since: August 4, 2011 Posts: 46 Comments: 4488
163. WeatherNerdPR
1:06 AM GMT on February 07, 2012
Quoting HurricaneDean07:

what, it not show up?

Yes it did show up, but I didn't want the quote to be so long, so I only put the first sentence of your comment.
Member Since: July 7, 2010 Posts: 0 Comments: 5725
162. HurricaneDean07
1:04 AM GMT on February 07, 2012
Quoting WeatherNerdPR:


what, it not show up?
Member Since: October 3, 2010 Posts: 40 Comments: 4129
161. WeatherNerdPR
1:03 AM GMT on February 07, 2012
TC Cyril...
Member Since: July 7, 2010 Posts: 0 Comments: 5725
160. KEEPEROFTHEGATE (Mod)
1:03 AM GMT on February 07, 2012
Quoting WeatherNerdPR:

maybe somebody dancing with Lucy in the Sky with Diamonds
Member Since: July 15, 2006 Posts: 176 Comments: 55665
158. bappit
12:57 AM GMT on February 07, 2012
Quoting Skyepony:
Looks like moderate chaff down by the keys tonight. That whispy on radar where there is no clouds..

Guess they don't want people to know what they are doing?
Member Since: May 18, 2006 Posts: 10 Comments: 6147
156. BDAwx
12:50 AM GMT on February 07, 2012
Cyclone Jasmine coming into view on New Caledonia Radar courtesy of MeteoFrance. (Tiébaghi site)
Member Since: August 3, 2009 Posts: 51 Comments: 545
155. Skyepony (Mod)
12:46 AM GMT on February 07, 2012
Looks like moderate chaff down by the keys tonight. That whispy on radar where there is no clouds..
Member Since: August 10, 2005 Posts: 209 Comments: 39113
154. Ameister12
12:45 AM GMT on February 07, 2012
Wow! That's beautiful.
Member Since: August 9, 2009 Posts: 10 Comments: 5080
153. Skyepony (Mod)
12:42 AM GMT on February 07, 2012
Radiation network. Little higher is spots tonight.
Member Since: August 10, 2005 Posts: 209 Comments: 39113
Quoting bappit:
#110

"Nuclear experts remain concerned about the structural integrity of the pool in which spent fuel is kept; if this pool were to collapse, it could produce a catastrophe worse than the meltdowns of the plant’s three reactors."

That's a nice tidbit. Godzilla's up to some mischief that's for sure.

Member Since: July 7, 2010 Posts: 0 Comments: 5725
Quoting JrWeathermanFL:
Slow blog.


this is normal for the off season....just seems slow after yesterdays' hype on 90L :D
Member Since: August 4, 2011 Posts: 46 Comments: 4488
#110

"Nuclear experts remain concerned about the structural integrity of the pool in which spent fuel is kept; if this pool were to collapse, it could produce a catastrophe worse than the meltdowns of the plant’s three reactors."

That's a nice tidbit. Godzilla's up to some mischief that's for sure.
Member Since: May 18, 2006 Posts: 10 Comments: 6147
Me:So, will the 2012 Hurricane season be active?
Cleverbot: Yes they will, they'll come to get you.
Me: How many hurricanes will hit?
Cleverbot: All.

O_O OMG, DOOMSDAY! 2012 will KILL US ALL! XD
Member Since: October 3, 2010 Posts: 40 Comments: 4129
Slow blog.
Member Since: Posts: Comments:
Beautiful day here in Mid TN.. grey skies finally cleared this afternoon, high in the 60's.. love it..
Got to go take pictures of the food at a bbq place down the street..(I'm building their website) Thank god I took my kids with me, they just kept bringing our plates of food and we'd take pictures and pass to plates to the kids.. I came home with 9 cartons of left-overs, ribs, pulled pork, chicken, baked beans, coleslaw etc etc etc.. I love my job!
Member Since: Posts: Comments:
While Punxsutawny Phil predicts six more weeks of Winter, CPC's CFSv2 predicts at least 4-6 more months of La Nina.

Weekly ENSO Update 6. February 2012
Member Since: Posts: Comments:
For West Palm Beach...

Member Since: Posts: Comments:
time to go eat a pizza be back soOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOon lol
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Quoting JrWeathermanFL:

Invest 97P most likely.


ya probably
Member Since: August 4, 2011 Posts: 46 Comments: 4488
HAHAHAHAHAHAHAHAHAHA!!!!!!!!!!!
________________________________________________

User: What is the name of the girl that I currently like?

Cleverbot: I don't like a girl, I like a boy.

User: I am talking about me, what girl do I like?

Cleverbot: So, your name is Lion.

User: What is her name?

Cleverbot: Who?

User: The girl that I like.

Cleverbot: Who is the girl that you love?

User: Yes, what is her name?

Cleverbot: Justin Bieber.

User: Oh god no....

Cleverbot: O god yes.

User: .....

Cleverbot: What?

User: Justin Bieber is a girl, but that isn't who I am talking about.

Cleverbot: Justin Bieber is a girl, haven't you heard her voice?
Member Since: September 3, 2011 Posts: 13 Comments: 3477
Quoting SPLbeater:
And here we have TC 11P in the SE Pacific...


CORRECTION: this is not 11P; its some random swirl lol

Invest 97P most likely.
Member Since: Posts: Comments:
And here we have TC 11P in the SE Pacific...


CORRECTION: this is not 11P; its some random swirl lol
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Quoting WxGeekVA:


We all need to see a dancing llama once in a while to lighten the mood!

Thomas and Friends old theme song...how i miss it.
Member Since: Posts: Comments:
Quoting WxGeekVA:


But that was before satellites...


Still, any missed storms just swirled out to sea harmlessly...
Member Since: Posts: Comments:


We all need to see a dancing llama once in a while to lighten the mood!
Member Since: September 3, 2011 Posts: 13 Comments: 3477
Quoting JrWeathermanFL:
The Western GOM storm has a cirrculation on it! Visible proves it!
Its heading south.


cute little thing..
Member Since: August 4, 2011 Posts: 46 Comments: 4488
The Western GOM storm has a cirrculation on it! Visible proves it!
Its heading south.
Member Since: Posts: Comments:

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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.