Irene's rains heaviest on record in Vermont; Tropical Storm Katia forms

By: Dr. Jeff Masters , 3:40 PM GMT on August 30, 2011

Share this Blog
29
+

Record flooding continues in the Northeast from Irene's torrential rains. Hardest hit was Vermont, where heavy rains in the weeks prior to Irene's arrival had left soils in the top 20% for moisture, historically. Irene dumped 5 - 8 inches of rain over large sections of Vermont, with a peak of 11.23" at Mendo. The reading from Mendo was the greatest single-day rainfall in Vermont's history, according to wunderground's weather historian Christopher C. Burt, beating the 9.92" that fell at Mt. Mansfield on 9/17/1999 during the passage of Tropical Storm Floyd. The 13.30" that fell on East Durham, NY during Irene was just shy of New York State's all-time 1-day rainfall record: 13.70" at Brewster on 9/16/1999, from Tropical Storm Floyd.


Figure 1. Wunderphotographer 43BJAGER recorded this image of a house in Sharon, Vermont, that started out the week on the other side of this underpass.

According to the final Hurricane Irene summary from the NWS, the storm dropped 20" of rain in two locations, one in North Carolina and one in Virginia. Here are the highest rain amounts from the hurricane for each state:

Virginia Beach, VA: 20.40"
Jacksonville, NC: 20.00"
East Durham, NY: 13.30"
Freehold Twp, NJ: 11.27"
Mendon, VT: 11.23"
Ellendale, DE: 10.43"
New Hartford, CT 10.15"
Baxter St. Park, ME: 9.91"
Savoy, MA: 9.10"
Lafayette, PA: 8.82"
Pinkham North, NH: 7.33"
Warren, RI: 5.37"

Tropical Storm Katia forms
Tropical Storm Katia formed this morning in the far Eastern Atlantic off the coast of Africa. Katia will be in a moist, low wind shear environment with ocean temperature 1 - 2°C above the threshold needed to support a hurricane, and should be able to intensify to major hurricane strength when it passes to the north of the Lesser Antilles Islands 5 - 6 days from now. It is possible that some of the outer spiral bands of the storm might bring heavy rain squalls to the northern Lesser Antilles, but it would be a surprise if the core of the storm passed through the islands. The long term fate of Katia is unknown. Dr. Bob Hart's Historical Tropical Cyclone Probability web page suggests shows that tropical storms in Katia's current position have a 19% chance of hitting North Carolina, a 16% chance of hitting Canada, an 11% chance of hitting Florida, and a 47% chance of never hitting land.


Figure 2. The morning run of the GFS Ensemble prediction. The ensemble prediction was done by taking a lower-resolution version of the GFS model and changing the initial distributions of temperature, pressure, and humidity randomly by a few percent to generate an ensemble of 20 different computer projections of where Katia might go. The operational (highest-resolution) version of the GFS model (white line) is usually more accurate, but the ensemble runs give one an idea of the uncertainty in the forecast.

Katia is the 11th named storm this year, and comes a full twelve days before the half-way point of the Atlantic hurricane season. Climatologically, September 10 marks the half-way point. A typical hurricane season has just 10 - 11 named storms, so we've already had a whole season's worth of storms before reaching the half-way point. At this rate, 2011 will see 25 named storms, making it the 2nd busiest season on record, behind 2005. Katia's formation date of August 30 puts 2011 in 5th place for earliest date of arrival of the season's 11th storm. Only 2005, 1995, 1936, and 1933 had an earlier 11th storm.

Gulf of Mexico development possible late this week
Several of our best computer models for predicting formation of tropical cyclones, the GFS and ECMWF, are predicting that an upper level pressure interacting with a tropical wave now over the the Western Caribbean could combine to spawn a tropical depression in the Gulf of Mexico late this week or early next week. The formation location is likely to be off the coast of Louisiana or Texas, but the track of the system is hard to predict at this point.


Figure 3. Portlight volunteer Thomas Hudson clears a driveway yesterday in Hollywood, Maryland.

Portlight disaster relief effort in Maryland
Hurricane Irene heavily damaged the town of Hollywood, Maryland, when a tornado cut off electric power, water, and phone service. Portlight and Team Rubicon volunteers arrived before emergency personnel, after following up on a local tip. What they found was an isolated area whose plight was unknown to the larger community. Most residents were trapped at their homes by heavy debris. Portlight and Team Rubicon worked for two days to clear paths to each address, extract vehicles from debris, and cut down trees that constituted safety hazards. Portlight also instructed local residents how to operate and maintain chainsaws and safely clear debris. No other volunteer organizations or emergency personnel arrived at any time, and Portlight succeeded in meeting the specific needs of the underserved, unserved, and forgotten. Visit the Portlight blog to learn more; donations are always welcome.

I'll have a new post on Wednesday discussing if the evacuations and media hype surrounding Irene were excessive.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 615 - 565

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 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53Blog Index

Still a little surprised she is only at 60mph, given her continued strengthening appearance on satellite imagery.
Member Since: Posts: Comments:
Quoting MississippiWx:


La Nina...



Look at the cold pool left by Irene east of the Southeastern US coastline.
Member Since: Posts: Comments:
Katia up to 60mph now. At this rate, she'll be a hurricane by tomorrow morning. Gaining strength fast.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
BULLETIN
TROPICAL STORM KATIA ADVISORY NUMBER 7
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122011
500 PM AST TUE AUG 30 2011

...KATIA CONTINUES TO STRENGTHEN OVER THE EASTERN TROPICAL
ATLANTIC...



SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...12.7N 35.4W
ABOUT 750 MI...1210 KM W OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 20 MPH...32 KM/H
MINIMUM CENTRAL PRESSURE...997 MB...29.44 INCHES
Member Since: Posts: Comments:
Quoting Gatorstorm:
Does anyone know whether we are headed into a La Nina or El Nina pattern, or neutral?


La Nina...

Member Since: Posts: Comments:
Quoting Gatorstorm:
Does anyone know whether we are headed into a La Nina or El Nina pattern, or neutral?


We're in a Neutral phase right now, but there is a La Niña Watch out, and there is a good likelihood, in fact, a GREAT likelihood, that we will go back to La Niña for winter.

Quoting Tazmanian:
could ex TD 10 pull some in like we saw in 2005 ?



where TD 10 die out and when it found lower wind shear it be come TD 12 and well the rest you sould no lol


I doubt it, but anything is possible...
Member Since: Posts: Comments:
Quoting Gatorstorm:
Does anyone know whether we are headed into a La Nina or El Nina pattern, or neutral?


We're cold neutral, heading back into La Nina later this year.
Member Since: Posts: Comments:
NAM at 66hrs

Member Since: Posts: Comments:
I posted it just a little while ago, but I'll post it again. The ASCAT pass nailed Katia (surprisingly), and analyzed either 0 knots or 50 knots near the center (probably 0 knots).

Member Since: Posts: Comments:
Quoting NoVaForecaster:


Does it have any model support to re-develop?


Not that I've seen.
Member Since: Posts: Comments:
Does anyone know whether we are headed into a La Nina or El Nina pattern, or neutral?
Member Since: Posts: Comments:
Hearing that a tropical wave MAY develop into a tropical cyclone in the Gulf of Mexico doesn't make it sound like the system could become destructive. However, with ridging to the north and east, whatever develops, IF it develops, could get stuck in the Gulf of a while...That would NOT spell good news if conditions permitted.
Member Since: Posts: Comments:


(UW-CIMSS have some issues with maps on occasion, I know, but)

That's an interesting set up for the moment.

This is for 400-850mb, so a bit ahead of where Katia is now. If she decides to intensify quicker than anticipated, then that set-up is a little similar to Carrie of '57.
Member Since: Posts: Comments:
First time Ive seen the majority of the models in good agreement so far out in a while
Member Since: Posts: Comments:
could ex TD 10 pull some in like we saw in 2005 ?



where TD 10 die out and when it found lower wind shear it be come TD 12 and well the rest you sould no lol
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
18z SHIPS only analyzed 5 knots of wind shear over Katia. CIMSS analyzed a weak anticyclone in the vicinity of the cyclone at 18z as well.


The outflow pattern is becoming much better. She is still elongated, but that's improving nicely.
Member Since: Posts: Comments:
Quoting thedawnawakening3:


ExTD10 would have to intensify rapidly and grow real deep before any of that were to happen. Right now that low level circulation is heading westward.


Talking about Katia. ExTD10 doesn't really have anything to do with it.
Member Since: Posts: Comments:
Quoting Katia:


Taz, where will I blow?




CA
Member Since: Posts: Comments:
Quoting NoVaForecaster:


Possible mini Fujiwara effect?

Loop:

Link


There won't be a Fujiwara unless that little swirl becomes a tropical cyclone...a tropical cyclone with a good bit of strength.
Member Since: Posts: Comments:
18z SHIPS only analyzed 5 knots of wind shear over Katia. CIMSS analyzed a weak anticyclone in the vicinity of the cyclone at 18z as well.
Member Since: Posts: Comments:
Has anyone figured out if certain storms or the environments surrounding them are more or less conducive to said storms propensity to wobble?
Member Since: Posts: Comments:
Quoting Cotillion:


She'd just go more north than currently anticipated.


ExTD10 would have to intensify rapidly and grow real deep before any of that were to happen. Right now that low level circulation is heading westward.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
18z NAM at 60 hours. This is yet another time this season where the NAM has been very consistent on developing a tropical cyclone. While the GFS and Euro have been back and forth, the NAM keeps on developing the system. However, I believe the NAM may be a bit too quick on development.

Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:


It would send the track farther north than expected...


okay thanks
Member Since: Posts: Comments:
Member Since: Posts: Comments:
i think mode runs still a little bit of a out lineer
Member Since: Posts: Comments:
Quoting HuracanTaino:
No, unless she is at 35N=13W at 5:00pm.


She is pretty darn close...35W, 12.5N.
Member Since: Posts: Comments:
Quoting ackee:
DO U guys think KAtia has been following the NHC track ?
No, unless she is at 35N=13W at 5:00pm.
Member Since: Posts: Comments:
Quoting interstatelover7165:
POLL

What size is Katia?...

A.Small
B.Medium
C.Large
D.Larger/Smaller
What Will Katia Be In 12 Hours?
A.50-60MPH
B.65 MPH
C.70 MPH
D.75 MPH...CAT1
E.Higher/Lower


B
C
Member Since: Posts: Comments:
Quoting ncstorm:
If Katia reaches hurricane strength before tomorrow, wouldnt that throw a wrench in the track..the models dont have it a hurricane until later..


She'd just go more north than currently anticipated.
Member Since: Posts: Comments:
Quoting MississippiWx:


Not unless it strengthens, which the chances of that are low. However, if it were to somehow flare back up and become a tropical cyclone again, there would likely be interaction between it and Katia. I wouldn't worry about that happening too much, but it's just something else to peak our interests.



ok
Member Since: Posts: Comments:
Yep...shear is DEFINATELY decreasing at a good clip around Katia
Member Since: Posts: Comments:
Quoting Tazmanian:





could that chang the track of TS with ex TD 10 out front


Not unless it strengthens, which the chances of that are low. However, if it were to somehow flare back up and become a tropical cyclone again, there would likely be interaction between it and Katia. I wouldn't worry about that happening too much, but it's just something else to peak our interests.
Member Since: Posts: Comments:
Quoting ncstorm:
If Katia reaches hurricane strength before tomorrow, wouldnt that throw a wrench in the track..the models dont have it a hurricane until later..


It would send the track farther north than expected...
Member Since: Posts: Comments:
Quoting MississippiWx:
The low level swirl out in front of Katia is what's left of TD10. It probably will just move off to the west and die out, but it will be interesting to see if maybe it can fire up a little convection tonight during d-max. It's approaching 50W, so the conditions at the surface will be supportive.






could that chang the track of TS with ex TD 10 out front
Member Since: Posts: Comments:
If Katia reaches hurricane strength before tomorrow, wouldnt that throw a wrench in the track..the models dont have it a hurricane until later..
Member Since: Posts: Comments:
The low level swirl out in front of Katia is what's left of TD10. It probably will just move off to the west and die out, but it will be interesting to see if maybe it can fire up a little convection tonight during d-max. It's approaching 50W, so the conditions at the surface will be supportive.

Member Since: Posts: Comments:

Viewing: 615 - 565

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 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53Blog Index

Top of Page

About

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

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron