Winter forecast for the U.S.; Typhoon Mirinae threatens the Philippines

By: Dr. Jeff Masters , 1:18 PM GMT on October 28, 2009

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Expect a warmer than average winter in the north central U.S., and cooler than average over the Southeast U.S., according the latest winter forecast issued last Thursday by the National Oceanic and Atmospheric Administration (NOAA). Wetter than average conditions are likely from Texas across the Gulf Coast and across the Southeastern U.S., with California also more likely than not to get increased precipitation. Those are the temperature patterns observed about 60% of the time in the U.S. during an El Niño event. As I discussed in yesterday's post, El Niño--the periodic warming of the equatorial Eastern Pacific Ocean that occurs every 2 - 7 years--has just crossed the threshold from weak to moderate, meaning that that ocean temperatures are 1.0 - 1.5°C above average along the Equator off the Pacific coast of South America. Moderate El Niño conditions are expected to continue through the winter months of December - February, with some climate forecast models predicting intensification into a strong El Niño. The presence of all that warm water alters the path of the jet stream, affecting the winter weather across a large portion of the globe. In particular, the southern branch of the jet stream--called the subtropical jet--is expected to intensify, bringing increased cloudiness and storminess along its usual path, from south Texas, across the Gulf Coast, through Florida, and into South and North Carolina. The increased cloudiness typically leads to cooler temperatures and more rainfall across the entire Southeastern U.S., especially Florida and South Texas. This should give significant drought relief to the South Texas.

The heat in the Eastern Pacific Ocean during an El Niño winter makes for more intense mid-latitude low pressure systems off the U.S. west coast. As a result, these storms are able to pump abnormally warm air into western Canada, Alaska and the extreme northern portion of the contiguous United States. With this warm air typically comes drier than normal conditions. With the forecast for Vancouver, Canada--home to the February 12 - 28 2010 Winter Olympics this winter--calling for warmer and drier conditions than average, lack of snow may be a problem for some of the venues. If the El Niño manages to strengthen to the strong category (greater than 1.5°C), California will most likely experience much increased precipitation, and the North Central U.S. will see winter temperatures 3 - 6°F above average. NOAA maintains a web page that shows the typical U.S. temperature and precipitation patterns for any season for historical EL Niño and La Niña events. Golden Gate Weather takes the idea a step further, and separates the effects by whether it is a weak, moderate, or strong El Niño.

How good is this forecast?
Not all El Niño winters follow the usual pattern. For instance, the El Niño winter of 2004 - 2005 had above-average temperatures over the entire U.S., and drier than average conditions across Florida, which are the opposite of the typical pattern observed during most El Niño winters (Figures 1 and 2). There are other natural variations in the weather and climate, such as the Pacific Decadal Oscillation (PDO) and the North Atlantic Oscillation (NAO) that can act to counteract or re-enforce the typical El Niño pattern. In addition, the climate is changing due to human-caused emissions of greenhouse gases, and its possible that what we've come to expect an El Niño winter to be like based on past history will no longer be true as often. It is likely the dramatic loss of arctic sea ice in recent years is already significantly affecting precipitation and temperature patterns during winter, and that the patterns we expect to see during El Niño winters are now changing to a new mode. I'll discuss the possibilities in a future post.


Figure 1. Wintertime (December - February) temperatures for the U.S. over the past nine years. The past three winters with El Niño conditions (yellow highlighted years) were 2003, 2005, and 2007. The 2003 El Niño was moderate strength, and 2005 and 2007 were weak. Image credit: National Climatic Data Center.

Figure 2. Wintertime (December - February) precipitation for the U.S. over the past nine years. The past three winters with El Niño conditions (yellow highlighted years) were 2003, 2005, and 2007. The 2003 El Niño was moderate strength, and 2005 and 2007 were weak. Image credit: National Climatic Data Center.

Philippines prepare for Typhoon Mirinae
Category 2 Typhoon Mirinae continues to trek westward towards the Philippine Islands, but appears to have leveled out in intensity. Latest infrared satellite loops show a large, well organized cloud pattern, but an eye is not evident, and the areal extent, organization, and temperature of the cloud tops has not changed much over the past six hours. Satellite estimates of Mirinae's intensity have held steady over the past twelve hours. Wind shear is a moderate 15 knots, and the ocean temperatures are very warm, 29°C. These warm waters extend to great depth, and the Tropical Cyclone Heat Potential (TCHP) is 80 - 100 kJ/cm^2 along Mirinae's entire path to the Philippines. Values of TCHP in excess of 90 kJ/cm^2 are frequently associated with rapid intensification. With wind shear expected to remain in the low to moderate range over the next three days, intensification of Mirinae into a major Category 3 or higher typhoon before its expected landfall at 06 UTC October 31 on Luzon Island is a good possibility.


Figure 4. Mirinae on October 27, 2009, as a tropical storm with 55 mph winds. Image credit: NASA.

Quiet in the Atlantic
There are no threat areas in the Atlantic to discuss, and the the Caribbean is dominated by dry air and high wind shear. However, the extreme Southwestern Caribbean near the coast of Panama is expected to gradually moisten early next week, and several recent runs of the GFS and NOGAPS models suggested that a tropical depression could form in the Southwest Caribbean off the coast of Panama 7 - 8 days from now.

Next post
In tomorrow's port, I'll discuss the impact of El Niño on wintertime tornado activity in Florida, plus have an update on the Philippines typhoon, and the latest model predictions of a possible tropical depression in the Caribbean next week.

Jeff Masters

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314. HadesGodWyvern (Mod)
you're welcome

ya the wind speed is low for a T5.0 system which should be around 90-95 kts
Member Since: May 24, 2006 Posts: 51 Comments: 45643
313. xcool
tornadodude not me all i do is pay bills
Member Since: September 26, 2009 Posts: 2 Comments: 15684
Quoting PcolaDan:




I liked Grothar's explanation :P
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting eyesontheweather:
Is it safe to believe that since your screen name is PcolaDan that you live in the pensacola fl area?

Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting NRAamy:
Am I the only one who is going to stick their neck out and ask if there was any beverage with atkins

hahahahahahahahahahaha!!!

yes, I normally drink my lunch....

;)

hence, my posts and why I get banned....
WOW 11 ha's
Member Since: August 25, 2008 Posts: 0 Comments: 633
Quoting HadesGodWyvern:
85 kts (CAT 2 on SSHS)


It looks a lot stronger, but I just guess that is because it is just a big storm. Thanks.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
Quoting Grothar:


Don't give up hope! The evening is young.


:( lol
Member Since: June 28, 2006 Posts: 25 Comments: 8360
oh well work = money

not in Calif it doesn't....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
Quoting tornadodude:
hey guys, glad to see im not banned :P


Don't give up hope! The evening is young.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
Quoting xcool:
tornadodude good. work at lot very tired.


oh well work = money (:
Member Since: June 28, 2006 Posts: 25 Comments: 8360
304. HadesGodWyvern (Mod)
85 kts (CAT 2 on SSHS)
Member Since: May 24, 2006 Posts: 51 Comments: 45643
please don't use the F word....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
302. xcool
tornadodude good. work at lot very tired.
Member Since: September 26, 2009 Posts: 2 Comments: 15684
301. tornadodude
9:04 PM GMT on October 28, 2009
.
Member Since: June 28, 2006 Posts: 25 Comments: 8360
300. Grothar
9:03 PM GMT on October 28, 2009
Does anyone know what Cat the Wpac storm is up to yet.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
299. tornadodude
9:02 PM GMT on October 28, 2009
Quoting xcool:
yay matt


haha how are you, Scott?
Member Since: June 28, 2006 Posts: 25 Comments: 8360
298. NRAamy
9:02 PM GMT on October 28, 2009
Am I the only one who is going to stick their neck out and ask if there was any beverage with atkins

hahahahahahahahahahaha!!!

yes, I normally drink my lunch....

;)

hence, my posts and why I get banned....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
297. Grothar
9:01 PM GMT on October 28, 2009
Quoting NRAamy:
eyes...I don't think ANYTHING is safe on this blog.....

;)


I thought his handle was he like PepsiCola.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
296. xcool
9:00 PM GMT on October 28, 2009
yay matt
Member Since: September 26, 2009 Posts: 2 Comments: 15684
295. Grothar
9:00 PM GMT on October 28, 2009
Quoting HadesGodWyvern:
gonna repeat myself..

believe PAGASA stated that if a cyclone got a local name people would be more alerted to take precautions

PAGASA also names Tropical Depression that JMA would not assign a name to


Oh, always wondered why. Makes sense. Probably works on the psychology of the local people so they can identify with it. Thanks.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
294. eyesontheweather
8:58 PM GMT on October 28, 2009
Quoting NRAamy:
I left to eat my Atkins lunch....
Am I the only one who is going to stick their neck out and ask if there was any beverage with atkins
Member Since: August 25, 2008 Posts: 0 Comments: 633
293. HadesGodWyvern (Mod)
8:58 PM GMT on October 28, 2009
gonna repeat myself..

believe PAGASA stated that if a cyclone got a local name people would be more alerted to take precautions

PAGASA also names Tropical Depression that JMA would not assign a name to
Member Since: May 24, 2006 Posts: 51 Comments: 45643
292. tornadodude
8:57 PM GMT on October 28, 2009
hey guys, glad to see im not banned :P
Member Since: June 28, 2006 Posts: 25 Comments: 8360
291. NRAamy
8:56 PM GMT on October 28, 2009
eyes...I don't think ANYTHING is safe on this blog.....

;)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
290. eyesontheweather
8:54 PM GMT on October 28, 2009
Quoting PcolaDan:


Hi just passing thru ...
Is it safe to believe that since your screen name is PcolaDan that you live in the pensacola fl area?
Member Since: August 25, 2008 Posts: 0 Comments: 633
289. 2ifbyC
8:50 PM GMT on October 28, 2009
Quoting pearlandaggie:
in case you haven't heard....flat-earthers don't have radios or tv or the internets....LOL


YES we do, thank you! Gawd, I love line-of-sight... without all the buildings...

Now, if ya would, please take your foot off the string. I'm trying to call the mods to report ya'll...
Member Since: September 18, 2005 Posts: 0 Comments: 254
288. NRAamy
8:44 PM GMT on October 28, 2009
No one ever did answer my question as to why they rename Pacific storms when they approach the Philippines?

I could tell you ...but then I'd get banned for sure....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
287. Grothar
8:42 PM GMT on October 28, 2009
Quoting NRAamy:
Grothar...yeah, sure...you're as pure as the driven snow...and I'm really an 18 year old blonde....

SQUAWK!!!!

:)


What made it funny, is that the remarks were truly innocent! It made my day. No one ever did answer my question as to why they rename Pacific storms when they approach the Philippines?
Member Since: July 17, 2009 Posts: 71 Comments: 26527
286. eyesontheweather
8:41 PM GMT on October 28, 2009
Quoting NRAamy:
Grothar...yeah, sure...you're as pure as the driven snow...and I'm really an 18 year old blonde....

SQUAWK!!!!

:)
it looks purple from here
Member Since: August 25, 2008 Posts: 0 Comments: 633
285. PcolaDan
8:39 PM GMT on October 28, 2009
Quoting NRAamy:
hey dashboard-cow dan!

:)


Hi just passing thru ...
Member Since: August 22, 2008 Posts: 12 Comments: 6010
284. NRAamy
8:39 PM GMT on October 28, 2009
Grothar...yeah, sure...you're as pure as the driven snow...and I'm really an 18 year old blonde....

SQUAWK!!!!

:)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
283. Grothar
8:39 PM GMT on October 28, 2009
Quoting PcolaDan:


Oh, yeah, Mr. Innocent is back. What is your question, Dan?
Member Since: July 17, 2009 Posts: 71 Comments: 26527
282. Grothar
8:37 PM GMT on October 28, 2009
Quoting NRAamy:
I left to eat my Atkins lunch....


Amy, maybe you better switch diets. I don't think we can't take much more. My sides are still hurting from this morning. Of course, I had absolutely no part of anything. I was just an innocent by-stander.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
281. SQUAWK
8:33 PM GMT on October 28, 2009
Shame I had to really work today. I missed all the fun.

AMY!!!!
Member Since: December 9, 2008 Posts: 0 Comments: 2498
280. NRAamy
8:31 PM GMT on October 28, 2009
hey dashboard-cow dan!

:)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
279. PcolaDan
8:30 PM GMT on October 28, 2009
is it safe?????
Member Since: August 22, 2008 Posts: 12 Comments: 6010
278. xcool
8:29 PM GMT on October 28, 2009
OJ
Member Since: September 26, 2009 Posts: 2 Comments: 15684
277. NRAamy
8:25 PM GMT on October 28, 2009
I left to eat my Atkins lunch....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
276. eyesontheweather
8:24 PM GMT on October 28, 2009
Quoting Grothar:


Where did everyone go? Laughed themselves out?
Lost breathe from laughing and.......or were banned. Very true about Philipines.
Member Since: August 25, 2008 Posts: 0 Comments: 633
275. necanicumwoman
8:23 PM GMT on October 28, 2009
Looking at the temperature and precipitation patterns for el Nino and la Nina years, it's hard to see how you can predict much of anything from these! For instance, 2005 el Nino and 2006 la Nina look identical! I think one problem is that the calendar year doesn't coincide with the weather year. Do the maps indicate statistics for the calendar year? This doesn't seem to be very helpful, since these events don't conveniently and suddenly start in January. Please elucidate.
Member Since: July 18, 2004 Posts: 0 Comments: 4
274. Grothar
8:21 PM GMT on October 28, 2009
Quoting eyesontheweather:
I don't think there is anyone else here. must be beautiful weather everywhere




Doesn't look too beautiful to the Philippines.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
273. Grothar
8:19 PM GMT on October 28, 2009
Quoting pearlandaggie:
269. nope! LOL


Then what are you doing here? I was lurking until I found a quiet moment. Laughed so hard on the morning blog, I had to leave.
Member Since: July 17, 2009 Posts: 71 Comments: 26527
272. Grothar
8:16 PM GMT on October 28, 2009
Quoting eyesontheweather:
I don't think there is anyone else here. must be beautiful weather everywhere


Where did everyone go? Laughed themselves out?
Member Since: July 17, 2009 Posts: 71 Comments: 26527
271. eyesontheweather
8:14 PM GMT on October 28, 2009
Quoting Grothar:
Is it safe to come back on the blog?
I don't think there is anyone else here. must be beautiful weather everywhere
Member Since: August 25, 2008 Posts: 0 Comments: 633
270. pearlandaggie
8:10 PM GMT on October 28, 2009
269. nope! LOL
Member Since: September 14, 2007 Posts: 3 Comments: 3963
269. Grothar
8:09 PM GMT on October 28, 2009
Is it safe to come back on the blog?
Member Since: July 17, 2009 Posts: 71 Comments: 26527
268. eyesontheweather
7:49 PM GMT on October 28, 2009
Press, have you taken your boat on some serious journy's or do you stay close to home. I grew up sailing Galvaston Bay myself and rarely journied to far from home. Farthest being aboout 7 miles out to some rigs. Have seen numerous porposis's and been caught in some very frieghtful weather.
Member Since: August 25, 2008 Posts: 0 Comments: 633
267. xcool
7:42 PM GMT on October 28, 2009



Member Since: September 26, 2009 Posts: 2 Comments: 15684
266. potteryX
7:35 PM GMT on October 28, 2009
BBL
265. potteryX
7:32 PM GMT on October 28, 2009
Chaser.
Living in the ITCZ is rather dull, actually.
The climate is generally dry season Jan-May, wet season June-Dec. When the ITCZ is overhead we can get a week of rainy days and ocasional heavy stuff. Seldom any wind.
Hurricanes and Storms that pass north of us can give us feedr bands that are sometimes severe.
This year has been quite dry. And we expect water-woes in the dry season if we dont get a lot of rain between now and Jan.
A news report from Venezuela (Caracas) is saying that the dam that powers the electric generators for the city is very low, and Caracas may have to load-shed if the dam does not fill.
Strange weather all round....
264. eyesontheweather
7:32 PM GMT on October 28, 2009
Quoting presslord:
I simply cannot express to you how badly I wish there were more to the story...
You are definatly a better man than I........I would have made something up and stuck to it!
Member Since: August 25, 2008 Posts: 0 Comments: 633

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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.