The Atlantic hurricane season is effectively over; heavy rains in the Northwest

By: Dr. Jeff Masters , 3:22 PM GMT on November 16, 2009

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Only two weeks remain in the Atlantic hurricane season, but the hurricane season of 2009 is effectively over. While the Western Caribbean is still warm enough to support development of a hurricane--as it is year-round--wind shear over the entire North Atlantic has risen to levels prohibitively high for tropical storm formation to occur. Wind shear is forecast to remain very high for at least the next ten days (Figure 1). This is a fairly typical occurrence in the Atlantic for this time of year, though it usually occurs sooner in El Niño years. As you probably know, El Niño conditions in the Eastern Pacific commonly create high levels of wind shear over the tropical Atlantic. This year was no exception, though the shear created by El Niño was not as strong as we've seen in other recent El Niño years. Wind shear was uncharacteristically low in the first half of November, allowing Hurricane Ida to form. Within the past ten days, though, El Niño conditions over the Eastern Pacific have intensified from moderate to strong, and wind shear over the tropical Atlantic has increased significantly, making it unlikely any significant tropical cyclones that affect land will occur the remainder of this hurricane season. Formation of a subtropical storm over the open Atlantic far from land is still a possibility, but such a storm would only be a concern to shipping.


Figure 1. Wind shear forecast for the Atlantic for ten days from now made by last night's 00Z run of the GFS model. The GFS model is forecasting very high wind shear over the entire North Atlantic over the next ten days.

Late season tropical storms in El Niño years
In the 17 hurricane seasons since 1950 where an El Niño event has been present, only three of those years featured named storms that formed after November 15. Tropical Storm Otto formed on November 29, 2004, from the remains of an extratropical storm that got cut off from the jet stream over the middle Atlantic. Otto meandered for a few days far from land before dissipating. Category 1 Hurricane Frances formed on November 19, 1986 in the open Atlantic south of Bermuda, and died after three days without affecting land. Category 1 Hurricane Martha formed on November 21, 1969 in the extreme southwestern Caribbean, off the coast of Panama. Martha weakened to a tropical storm before making landfall in Panama, and was the only named storm in the Atlantic ever to make landfall in Panama.

Typhoon season not over yet
Note that typhoon season in the Western Pacific is not over--we commonly get typhoons well into December. In fact, the ECMWF model is predicting formation of yet another typhoon east of the Philippines, sometime late this week or early next week. Tropical cyclone season is also not over in the Bay of Bengal near India, where some models are predicting an enhanced chance of a tropical storm forming late this week. And in the Southern Hemisphere, hurricane season is just beginning, with the formation of Category 3 Tropical Cyclone Anja near Maritius Island off the coast of Madagascar.


Figure 2. Category 3 Tropical Cyclone Anja in the South Indian Ocean at 1 am EST Monday November 16, 2009. Image credit: NASA.

Heavy rains hit Washington and British Columbia
A strong branch of the polar jet stream laden with moisture is streaming into Washington State and Canada's British Columbia today, and is forecast to bring heavy rains, high winds, and the threat of avalanches to the coastal mountains today through Wednesday. Heavy rains in the Pacific Northwest this time of year are often dubbed the "Pineapple Express" due to Hawaiian origin of the air, and these events are common during El Niño winters, and can strike from Southern California to British Columbia. However, I've been told by Doug McCollor, a forecaster with BC Hydro, that this rain event is not a true Pineapple Express, since the airflow is more west-to-east, rather than from the southwest. He adds, "also, freezing level at Quillayute WA was only 1800m this morning...not that high. In a Pineapple Express the freezing level would be 3500 to 4000m or so. The media here is calling it a Pineapple Express because they look out the window and it's raining all day. It is raining moderately here, no doubt, but it's because there is a downstream Rex block forming over central North America that is impeding the usual west-to-east progression of these storms".

Rainfall amounts in excess of three inches have already been recorded over Vancouver Island, and rains of up to seven inches (Figure 3) are forecast for the region over the next three days. Wind gusts of 44 mph have been recorded at La Push this morning on Washington's Olympic Peninsula.


Figure 3. Forecast precipitation for the 3-day period ending 7 am EST Thursday, November 19, 2009. Up to seven inches of rain are predicted for Washington State and coastal British Columbia. Image credit: NOAA/HPC.

I'll have a new post Tuesday or Wednesday.

Jeff Masters

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I'm always impressed when people find new ways to be ignored
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Quoting GeoffreyWPB:
316. PcolaDan 9:16 PM EST on November 16, 2009
Quoting Grothar:


I've been in an actual Arctic blast, above the Arctic Circle. Not fun. Try spending a winter in Northern Norway, you'll never want another one. lol


Minot, ND nuff said

On average, It gets colder in North Dakota than in Northern Norway during their respective winter seasons? Did not know that.


Well of course. They have water north of them in Norway, Minot has ........... CANADA!!!

Actually I was a little surprised at some of the number.
Minot:Average high temperature for January is 15 degrees, average temperature is 7 degrees. The average low temperature is two degrees below zero. The coldest temperature ever recorded here is 35 degrees below zero.

Norway:The coast experiences much milder winters than other areas at the same latitudes. The temperature difference from the coldest month to the warmest is only 11 - 15 °C in coastal areas; some lighthouses has a year amplitude of just 10 °C, such as Svinøy in Herøy with a coldest month of 2.7 °C [5]. The amplitude of inland areas are larger, with a maximum of 30 °C in Karasjok. Finnmarksvidda has the coldest winters in Norway, but inland areas further south can also see severe cold; Røros has recorded -50 °C and Tynset has a January average -13°C. Normal monthly averages range from -17.1 °C in January in Karasjok 129 m amsl.[6] to 17.3 °C in July in Oslo - Studenterlunden 15 m amsl.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
---
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hurricane season is over.

but guess what?

winter is rapidly approaching!
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hoosiers up 32-25 at halftime.
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The Atlantic hurricane season is effectively over
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The Atlantic hurricane season is effectively over
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The Atlantic hurricane season is effectively over
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316. PcolaDan 9:16 PM EST on November 16, 2009
Quoting Grothar:


I've been in an actual Arctic blast, above the Arctic Circle. Not fun. Try spending a winter in Northern Norway, you'll never want another one. lol


Minot, ND nuff said

On average, It gets colder in North Dakota than in Northern Norway during their respective winter seasons? Did not know that.
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Mount Washington (Our local Ski resort) had up to 3 feet of snow at the summit...

Alpine Snow Report for : Monday, November 16, 2009 @ 12:00 AM


Great news!! We're opening early on Saturday, November 28th. Our base is holding strong and the forecast this week is calling for another 50-60cms of snow....yeeehaaa!

We will be updating the snowbase with each successive snowfall so think snow! Official reporting with all the mountain details including lift and terrain openings will take place closer to our new opening date.

See you on the 28th!
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Don't forget Merv Griffin: "I will not
be back after these messages"
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To provide closure to the 2009 Hurricane Season, I'm proposing some notable epitaphs:

George Carlin (suggested by himself)
"Hey! He was just here a minute ago!"

George Johnson (unknown)
"Here lies George Johnson
Hanged by mistake, 1882
He was right
We was wrong
But we strung him up
And now he's gone"


Jeremiah Johnson (unknown)
"I told you I was sick."

Nikos Kazantzakis (by himself)
"Then elpizo tipota. The fovamai tipota. Eimai eleftheros." ("%u0394%u03B5%u03BD %u03B5%u03BB%u03C0%u03B9%u03B6%u03C9 %u03C4%u03B9%u03C0%u03BF%u03C4%u03B1. %u0394%u03B5 %u03C6%u03BF%u03B2%u03B1%u03BC%u03B1%u03B9 %u03C4%u03B9%u03C0%u03BF%u03C4%u03B1. %u0395%u03AF%u03BC%u03B1%u03B9 %u03B5%u03BB%u03B5%u03C5%u03B8%u03B5%u03C1%u03BF%u03C2")
Translation: "I hope for nothing. I fear nothing. I am free."

H. G. Wells (himself) - 1866-1946
"I told you so, you damned fools."

Proposed by Fields:
Here lies W. C. Fields. I would rather be living in Philadelphia.


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Quoting GeoffreyWPB:
An Artic blast down here is highs in the 50's. I know it is miserable for others. A conundrum for sure.


It's the humidity.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting Grothar:


I've been in an actual Arctic blast, above the Arctic Circle. Not fun. Try spending a winter in Northern Norway, you'll never want another one. lol


Minot, ND nuff said
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Hi Orca,

ok, i checked this earlier today and i swear it stated up to 2 feet friday now it says:

FRIDAY AND FRIDAY NIGHT...SIGNIFICANT SNOW IS POSSIBLE IN THE
SIERRA AND NORTH INTO LASSEN COUNTY. AROUND A FOOT OF SNOW IS POSSIBLE IN THE HIGH SIERRA AND NORTH INTO LASSEN AND PLUMAS COUNTIES WITH SEVERAL INCHES OF SNOW AT LAKE TAHOE LEVEL. LOCATIONS EAST OF THE SIERRA ABOVE 5000 FEET COULD RECEIVE UP TOA FEW INCHES OF SNOW LATE FRIDAY NIGHT. LOWER VALLEY LOCATIONS OF WESTERN NEVADA ALONG AND NORTH OF INTERSTATE 80 MAY RECEIVE A LIGHT ACCUMULATION OF SNOWFALL BY SATURDAY MORNING.

need some snow for the kiddie-kats to play in, not to mention the filling up the water supply!
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Towing of Virginia Beach barge delayed
"They must save the Rum."
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Quoting WaterWitch11:


hi,
sierra mountain are expected to get up to 2 feet of snow on friday.


What TS missed is the pineapple express is warm moist air from Hawaii. We won't get snow from it unless is collides with with an arctic cold front coming down from Alaska. The mountains will get some snow because its that time of year, and any moisture is basically going to be snow.. but the pineapple express normally raises the snow level by at least a 1000 feet.

For you Floridians... thats about 4000 oranges stacked on top of each other :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting Orcasystems:

That is Jeff's

Your opinion??


I agree but I would not rule out a stray subtropical system.
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An Artic blast down here is highs in the 50's. I know it is miserable for others. A conundrum for sure.
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Quoting TampaSpin:
Wow the Pineapple Express is coming with that Southern Jet Stream......You all up north better hope it does not get cold or your looking for a nice Winter mix coming.


hi,
sierra mountain are expected to get up to 2 feet of snow on friday.
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Quoting Weather456:
Hurricane season is effectively over

hmm

Yup it's a wrap.
Still, I'd rather be awake in maryland than dead in philadelphia.
lol.
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Quoting GeoffreyWPB:
We don't live that far apart...we are going to have similar temps. I love cold weather (since I have lived here all my life). I hope we have a few artic blasts come through here this season.


I've been in an actual Arctic blast, above the Arctic Circle. Not fun. Try spending a winter in Northern Norway, you'll never want another one. lol
Member Since: July 17, 2009 Posts: 71 Comments: 26009
We don't live that far apart...we are going to have similar temps. I love cold weather (since I have lived here all my life). I hope we have a few artic blasts come through here this season.
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Quoting Weather456:
Hurricane season is effectively over

hmm

That is Jeff's

Your opinion??
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting GeoffreyWPB:
But I do believe Ida was the last. No more this season.


Hey, Geoff, just kidding on the similar forecast!
Member Since: July 17, 2009 Posts: 71 Comments: 26009
But I do believe Ida was the last. No more this season.
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Glad you are feeling better 456!
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Hurricane season is effectively over

hmm
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I am under those blobs somewhere.


Seismic Monitor

AOI

AOI

Humor in Comments
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting KEEPEROFTHEGATE:
winds are light with this one rain is an issue from now till later tonight


Here is my weather station raw data
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting jeffs713:

You have my deepest condolences.

Orca - Since you live in the area, how do you expect El Nino to impact the snowfall potential for the winter games in your area?


We are hoping it will do as it normally does... and make for a lot of moisture... in the mountains.. thats snow, and lots of it. They are already thinking of opening the slopes a few weeks early.
Member Since: October 1, 2007 Posts: 81 Comments: 26511
imagine if this was over water 0_o perfect storm 3! (cause ida was number 2 of course)

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Quoting tornadodude:


I love the Colts and the Cowboys. :P

You have my deepest condolences.

Orca - Since you live in the area, how do you expect El Nino to impact the snowfall potential for the winter games in your area?
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Quoting AwakeInMaryland:

ROFL. Well, definitely they (and WS) would like to be chauffered (chauferred??) around. I cannot spell today, notice I spelled desert as dessert before!

Mr. T-Dude; a word?
You were a Pat's fan.
So NOW you're claiming your Indiana heritage???
Next it will be Cowboys because you were born there.

This can only lead to bloodshed.


Whoa whoa whoa! I have never claimed to like the Pats. I like the Red Sox, but not the Pats! haha I love the Colts and the Cowboys. :P
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RAINFALL WARNING: Greater Victoria Issued at 3:14 PM PST MONDAY 16 NOVEMBER 2009

ADDITIONAL RAINFALL AMOUNTS OF 20 TO 50 MM EXPECTED BY TUESDAY MORNING. THIS IS A WARNING THAT SIGNIFICANT RAINFALL IS EXPECTED OR OCCURRING IN THESE REGIONS. MONITOR WEATHER CONDITIONS..LISTEN FOR UPDATED STATEMENTS.

A SLOW MOVING PACIFIC FRONTAL SYSTEM OVER THE SOUTH COAST OF BRITISH COLUMBIA WILL CONTINUE TO BRING RAIN AT TIMES HEAVY OVER THE AREA TONIGHT. ADDITIONAL RAINFALL AMOUNTS OF 20 TO 50 MM CAN BE EXPECTED BY TUESDAY MORNING WITH HIGHEST AMOUNTS OVER HOWE SOUND AND NEAR THE NORTHSHORE MOUNTAINS. MEANWHILE, STRONG SOUTHERLY WINDS UP TO 70 KM/H WILL DEVELOP OVERNIGHT. THE WINDS ARE EXPECTED TO EASE TUESDAY MORNING AS THE FRONT MOVES INLAND.
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting atmoaggie:

Snark! That is prolly what I got in about 40 minutes...


I know.. you guys can do that in 30 minutes.. we are not confured that way with the mountain systems... 3" in a day is bad.. and 12" in two days is a disaster.

IF we get a foot between now and tuesday night.. it will fall heavy in the mountains... and down to the rivers.

Vancouver/Burnaby/Surrey/etc are all on the Fraser River Delta... not going to be pretty if the Fraser floods.

Its happened before..and when it does, a lot of people get flooded out.

Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting atmoaggie:

I was looking at the EPac wave heights...not spectacular. Some waves, certainly, but nothing like what you guys see when a big un does come up.
winds are light with this one rain is an issue from now till later tonight
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Quoting Orcasystems:
1.57" of rain so far since 9 am (3:53 pm now) and now its starting to rain like it means it.
Road is starting to act like a river

Snark! That is prolly what I got in about 40 minutes...
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Quoting Orcasystems:


Not even close... its right on time.. we do the pineapple express every year at this time. Basically just a rain event right now... when it has the 90 mile winds..then its big.

I was looking at the EPac wave heights...not spectacular. Some waves, certainly, but nothing like what you guys see when a big un does come up.
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Gotta run the Hoosiers play tonite on the Big Ten Network and then we have the best MNF game of the year on ....geeshhhhh....LOL...

Maybe Orca can get some snow falling on that game...BBL.
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Quoting TampaSpin:


Keeper that is an Ouchy.....that is very strong for this time of year.
the worst is yet to come ashore lots of water yet to come
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Quoting TampaSpin:


Keeper that is an Ouchy.....that is very strong for this time of year.


Not even close... its right on time.. we do the pineapple express every year at this time. Basically just a rain event right now... when it has the 90 mile winds..then its big.


That being said.. I would not want to be on the mainland in the Fraser Delta... not going to be pretty at all.
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting TampaSpin:


Keeper that is an Ouchy.....that is very strong for this time of year.


Heck i keep forgetting it is November.....this year has flew by.
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Quoting KEEPEROFTHEGATE:
here is loop of system slamming the west coast



Keeper that is an Ouchy.....that is very strong for this time of year.
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Funny i was just looking at the GFSX long range.....now i don't put alot of truth this far out but.....looks like one heck of a NOrEaster coming thru the Southern States and then up the EAST coast......hehehehehe


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Quoting GeoffreyWPB:
Hope that pans out Tim. When do you expect the fronts to start rolling through on a regular basis?

Like this one...enough convergence for a quick very hard rain, but eerily, no lightning. CAPE was nonexistent. Convergence was the driver, but has a limited vertical effect.

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here is loop of system slamming the west coast

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1.57" of rain so far since 9 am (3:53 pm now) and now its starting to rain like it means it.
Road is starting to act like a river
Member Since: October 1, 2007 Posts: 81 Comments: 26511
The models are expecting a nice negatively tilted shortwave trough to move into the SE U.S. next week. It seems that this system will have sufficient energy to bring florida some nice rain.
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Quoting GeoffreyWPB:
Hope that pans out Tim. When do you expect the fronts to start rolling through on a regular basis?


From that Southern Jet Stream and that big Low that is up Orca is gonna change some things in about 14 days across the North for sure.....
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Quoting GeoffreyWPB:


That would be a double bonus. Thanks canes.


No problem Geoffrey.
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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.

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