La Niña is here

By: Dr. Jeff Masters , 1:16 PM GMT on July 15, 2010

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The equatorial Eastern Pacific Ocean continues to cool, and we have now crossed the threshold into La Niña conditions. Sea surface temperatures (SSTs) over the tropical Eastern Pacific in the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region", fell to 0.8°C below average by July 12, according to NOAA.. The Australian Bureau of Meteorology put this number at 0.7°C below average (as of July 11.) Since La Niña conditions are defined as occurring when this number reaches 0.5°C below average, we are well into the territory of a weak La Niña event. La Niña conditions must be present for several months before this will be officially classified as a La Niña event, but it is highly likely that a full-fledged La Niña event lasting at least eight months has arrived. We started out the year with a strong El Niño, so it may seem surprising that we have transitioned La Niña so quickly, However, historically, about 35 - 40% of El Niño events are followed by a La Niña within the same year. Given current trends, I expect the current La Niña to cross the threshold needed to be defined as "moderate" strength--temperatures at least 1.0°C below average in the equatorial Eastern Pacific--by September.


Figure 1. Progression of El Niño to La Niña over the past year, as measured by SSTs in the the tropical Eastern Pacific in the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region". Image credit: NOAA Climate Prediction Center.

The implications
It is well-known that both the number and intensity of hurricanes in the Atlantic tend to increase during La Niña events. However, as I discussed in a post last month, since 1995, neutral years (when neither an El Niño or La Niña are present) have had Atlantic hurricane activity equal to La Niña years. The last time we had a strong El Niño event followed by a La Niña event in the same year, in 1998, we had a Atlantic hurricane season 40% above average in activity, with 14 named storms, 10 hurricanes, and 3 intense hurricanes. The season was relatively late-starting, with only one named storm occurring before August 20. I'm thinking this year's season may be similar, though four or more intense hurricanes are a good bet due to the record warm SSTs.

Both El Niño and La Niña events have major impacts on regional and global weather patterns. For the remainder of July and August, we can expect La Niña to bring cloudier and wetter than average conditions to the Caribbean, but weather patterns over North America should not see much impact (Figure 2.) Globally, La Niña conditions tend to cause a net cooling of surface temperatures. Thus, while the past twelve month period has been the warmest globally since record keeping began in 1880, it is unlikely that the calendar year of 2010 will set the record for warmest year ever.



Figure 2. Typical regional weather anomalies observed during June - August when La Niña conditions are present. The Caribbean tends to be cloudier and wetter than average, but there is typically little change to temperature and precipitation patterns over North America. Image credit: NOAA Climate Prediction Center.

The tropics are quiet
There are no threat areas to discuss in the Tropical Atlantic today, and none of the reliable computer models is calling for tropical cyclone development over the next seven days.

Next post
I'll have a new post on Friday.

Jeff Masters

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1799. KEEPEROFTHEGATE (Mod)
1794
wait i will knock on the roof
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00z Para GFS
"Mischief"

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Had some gusty winds here but nothing significant yet hopefully will stay that way.
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.
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Quoting 954FtLCane:

so basically more storms means more money!!


Y...yes.
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Quoting futuremet:


As site traffic continues to grow, this site is becoming more profitable. It is to WU's best interest to let bloggers join for free.




so basically more storms means more money!!
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Quoting futuremet:


As site traffic continues to grow, this site is becoming more profitable. It is to WU's best interest to let bloggers join for free.







i think 10% is all so from the trolls that come here
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1790. KEEPEROFTHEGATE (Mod)
hail and wind is pounding the windows you know who must be crappin his pants
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1789. Patrap
The Blogs are only a small slice of the wunderground traffic.

At best only 2-4 % of the server is used on a Busy day for the ZBlogs.

Most hits come from folks who seek the weather info globally.



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Quoting Tazmanian:



but its worth it it will cut down the trolls and jfv


As site traffic continues to grow, this site is becoming more profitable. It is to WU's best interest to let bloggers join for free.



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Quoting KEEPEROFTHEGATE:

ahhh perfect sleeping weather....
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1785. KEEPEROFTHEGATE (Mod)
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1784. leo305
Quoting hurricane23:


Recorded a 58mph gust 5-10 min ago with the anemometer outside the house.


Wow, that's crazy =O

how cool
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Quoting futuremet:


This blob is what makes the site very profitable. A large part of Wunderground's revenue comes from contextual advertising. The blog allows people to stay here longer. This increases the number of ad-clicks WU gets. Each ad-click generates revenue depending on the keyword, niche, and the amount the advertiser is willing to pay.

If WU did that, this will hinder potential growth in revenue.



but its worth it it will cut down the trolls and jfv
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Quoting scott39:
Ive had enough of this infintile garbage! Im going to E-Mail Admin and suggest they start charging a mandatory $10.00 every time you sign up under a new user name!That should slow this absurdity down instantly! Anyone else who would like to E-Mail Admin, with the same idea, is welcome to.


This blob is what makes the site very profitable. A large part of Wunderground's revenue comes from contextual advertising. The blog allows people to stay here longer. This increases the number of ad-clicks WU gets. Each ad-click generates revenue. The revenue depends on the keyword, niche, and the amount the advertiser is willing to pay.

If WU did that, this will hinder potential growth in revenue.
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Quoting leo305:
Wow.. downed power lines, and trees were broken apart around UM near gables.. 60mph winds are estimated with this storm


Recorded a 58mph gust 5-10 min ago with the anemometer outside the house.
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1779. Patrap
NEXRAD Radar
Miami, Velocity Azimuth Display Wind Profile Range 124 NMI


One can almost see the curtain go by.. here.


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1774. Uh oh dats me.
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1777. Patrap
NEXRAD Radar
Miami, Storm Relative Mean Radial Velocity 0.50 Degree Elevation Range 124 NMI

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1776. Patrap
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Quoting scott39:
Ive had enough of this infintile garbage! Im going to E-Mail Admin and suggest they start charging a mandatory $10.00 every time you sign up under a new user name!That should slow this absurdity down instantly! Anyone else who would like to E-Mail Admin, with the same idea, is welcome to.




thank you sir i 2nd that
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1774. Patrap

440
WUUS52 KMFL 160344
SVRMFL
FLC011-086-160430-
/O.NEW.KMFL.SV.W.0048.100716T0344Z-100716T0430Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
1144 PM EDT THU JUL 15 2010

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN BROWARD COUNTY IN SOUTH FLORIDA.
NORTHEASTERN MIAMI-DADE COUNTY IN SOUTH FLORIDA.

* UNTIL 1230 AM EDT

* AT 1139 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS HAVE
DETECTED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED
ALONG A LINE EXTENDING FROM 5 MILES SOUTHWEST OF MICCOSUKEE RESORT
TO MICCOSUKEE RESORT TO MIAMI LAKES TO NORTH MIAMI BEACH...AND
MOVING NORTHWEST AT 30 MPH.

* THE LINE OF STORMS WILL AFFECT...
CAROL CITY...
HOLLYWOOD...
INTERSECTION U.S. 27 PINES BLVD...
COOPER CITY...
DAVIE...
WESTON...
AND SURROUNDING COMMUNITIES.

POWER LINES AND TREES HAVE BEEN REPORTED DOWN WITH THIS THUNDERSTORM
IN HIALEAH AND CORAL GABLES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS CAN PRODUCE VERY STRONG WINDS IN EXCESS OF 60
MPH...SMALL HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAINFALL. STAY
INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.



LAT...LON 2583 8014 2586 8015 2587 8013 2590 8014
2586 8017 2581 8018 2567 8040 2586 8065
2611 8060 2612 8019 2594 8011 2584 8011
TIME...MOT...LOC 0343Z 136DEG 24KT 2574 8056 2582 8048
2594 8037 2594 8019
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Quoting MiamiHurricanes09:
Match that up with warm SSTs and upward motion you're bound to get an impulse of activity.


I am puzzled by what is causing the TUTT to lift out so fast. The GFS' forecast for a downward MJO phase seem to be contradicting itself. A downward phase in the MJO inhibits vertical motion in the tropics and the ITCZ--which causes the TUTT to dig farther south.
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1772. leo305
Quoting hunkerdown:
first off, it is just at 10% for development within the next 48. give it time, it is just an AOI that MAY have future possibility for development.


yes, but there have been so many of those lows in the central atlantic in the past couple of seasons, now is when they put circles around them?
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Quoting Cubanism:
Really? It's dead calm over here right now.



jfv give it a rest you are banned from the blogs evere name you come on here the Admin banneds it right up when the Admin banneds you that dos not mean come back on with a new ID that other name you had got banned that mean you got no rights too come right back on here with other name when some one banneds you that means your done gone banned mean you dont keep makeing new ids sooner or later the Admin is going too block you from the site and hoping that would keep you from makeing new IDS in fac i find it odd that he has not block you right now from the site this makeing new IDs has got too stop and it will stop sooner or later and i hop it dos be for the season gets vary busys



sorry all if some of that sounded a little rude but you no what this needs too stop
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1770. scott39
Quoting leo305:


yea idk what the NHC was thinking.. considering it has no model support, and the environment is definately not conducive for any development
You dont ignore a wave with that kind of structure.
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1769. leo305
Wow.. downed power lines, and trees were broken apart around UM near gables.. 60mph winds are estimated with this storm
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Quoting leo305:


yea idk what the NHC was thinking.. considering it has no model support, and the environment is definately not conducive for any development
first off, it is just at 10% for development within the next 48. give it time, it is just an AOI that MAY have future possibility for development.
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Is the SAL suppose to lessen any time soon??
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1764. leo305
Quoting Hurricanes101:


too much SAL for now


yea idk what the NHC was thinking.. considering it has no model support, and the environment is definately not conducive for any development
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1763. scott39
Quoting Tazmanian:
has soon has you banned him he comes right back with a new one and thats 2 names in one day
Ive had enough of this infintile garbage! Im going to E-Mail Admin and suggest they start charging a mandatory $10.00 every time you sign up under a new user name!That should slow this absurdity down instantly! Anyone else who would like to E-Mail Admin, with the same idea, is welcome to.
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Quoting Cubanism:
Gang, I'm gonna log out, I'm experiencing major down-burst winds over here right now, the weather has become quite severe all of the sudden.
hold that rod real tight, don't want to drop it...
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Quoting StSimonsIslandGAGuy:
I have to say, our east Atlantic wave is not building up convection. What time is it over where the wave is, 3:40 am? If D-max was coming into play, should have been doing something by now.
It will be a few days at least before there's any chance for a resemblance of development. So not having any convection now will not rule out the possibility of future development. Just keep one eye on it for now.
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Aren't you near Coral Gables MH?
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Quoting StSimonsIslandGAGuy:
I have to say, our east Atlantic wave is not building up convection. What time is it over where the wave is, 3:40 am? If D-max was coming into play, should have been doing something by now.


too much SAL for now
Member Since: March 10, 2010 Posts: 1 Comments: 8078
Quoting Hurricanes101:


I was going to ask if she had two circulations


Woah lol bringing out weather related double entandres.
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i so wish i was the Admin
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Quoting ElConando:


Did you pick up her spirits?


I was going to ask if she had two circulations
Member Since: March 10, 2010 Posts: 1 Comments: 8078
not adding to the mix....but we had a severe storm earlier and i didnt see any thunder...guess i need to eat more carrots n up my eye exam apointments
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Hearing lightning from time to time but no rain.
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1750. Patrap
Quoting ElConando:


Did you pick up her spirits?


I sailed right thru it actually.
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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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