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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Quoting MTWX:
If the oil is completely stopped and the valve holds, is there any reason to continue drilling the relief wells???


There is. The original BOP and well bore may have additional damage that could affect performance later. Either BP has to plug it permanently or they have to plug it until a new BOP and drilling set up can be installed should this well actually be productive later.
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Quoting MTWX:
If the oil is completely stopped and the valve holds, is there any reason to continue drilling the relief wells???


yes indeed... the cap is a Temp fix.


The relief wells can proceed once the Well bore is deemed safe to tap and pump in the bottom Kill fluids.

Thats the permanent fix.

Always
Member Since: July 3, 2005 Posts: 432 Comments: 132008
596. IKE
Gauges you see on ROV's are not for pressure in the well...per CNN.


Quoting MTWX:
If the oil is completely stopped and the valve holds, is there any reason to continue drilling the relief wells???


I thought about that too.

Oil is completely stopped.
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Quoting MTWX:
If the oil is completely stopped and the valve holds, is there any reason to continue drilling the relief wells???
yep this is temp plug if this procedure works . relief well is perm solution
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Quoting StormW:


Roughly 17N;35W


Thanks storm!!
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593. MTWX
If the oil is completely stopped and the valve holds, is there any reason to continue drilling the relief wells???
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Member Since: July 14, 2009 Posts: 51 Comments: 1731
Quoting Patrap:
Now the Trust is in the Stack.

If she can hold the pressure and the down hole bore is in-tact.

We may have diz mutha stopped.

Prayer's up.



ASAP.
AMEN!!!!!! Fingers Crossed!!!!
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Quoting 1fromnovasscotia:
just curious anyone know when the next update for trop storm conson will be?
5pm EDT. It should be around that time if not close after.
Member Since: July 14, 2009 Posts: 51 Comments: 1731
Storm or someone. Can you give me the Lat/Lon of this disturbance west of Cape Verde.
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585. IKE
BP shares up 10% after oil stopped.
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New Watch possible

Member Since: July 14, 2009 Posts: 51 Comments: 1731
just curious anyone know when the next update for trop storm conson will be?
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STOP! In the name of love...
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Quoting clwstmchasr:


He was pretty rough on Jeff but you have to admit that Jeff does get a bit carried away with everything coming to FL.


Ya think, That's Mr. Severe Weather.
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Fox news reporting oil has stopped.
Member Since: September 18, 2006 Posts: 0 Comments: 1335
Lets hope that the pressure of the oil beneath the cap will go up. (correct me if I'm wrong.)
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The One ROV is using the SONAR to scan the Sea Floor..

O' Man,,Drama-itis

Skandi_ROV 1
Member Since: July 3, 2005 Posts: 432 Comments: 132008
Quoting Patrap:
Now the Trust is in the Stack.

If she can hold the pressure and the down hole bore is in-tact.

We may have diz mutha stopped.

Prayer's up.



ASAP.


Can it be? I'm holding my breath!
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.."under Pressure"..
Member Since: July 3, 2005 Posts: 432 Comments: 132008
Quoting clwstmchasr:


He was pretty rough on Jeff but you have to admit that Jeff does get a bit carried away with everything coming to FL.


Yes he does, but I don't want everybody on here telling him that he is the worst forecaster, hes still learning on here as well as I am and others so everyone should stop jumping on him for being wrong.
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U betcha Ike..

Lets find a tune..
Member Since: July 3, 2005 Posts: 432 Comments: 132008
571. IKE
Quoting Patrap:
Now the Trust is in the Stack.

If she can hold the pressure and the down hole bore is in-tact.

We may have diz mutha stopped.

Prayer's up.



ASAP.


Amen. Best news I've heard all week.
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Now the Trust is in the Stack.

If she can hold the pressure and the down hole bore is in-tact.

We may have diz mutha stopped.

Prayer's up.



ASAP.
Member Since: July 3, 2005 Posts: 432 Comments: 132008
569. IKE
BREAKING NEWS! From CNN!

BP: No Oil is flowing into the GOM!
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Quoting Patrap:
BREAKING NEWS

The BOP Stack VALVES have stopped the Oil flow.

Thew Choke Line valve is closed 100%

FLASH TRAFFIC


Live feeds from the Gulf of Mexico ROVs


Excellent news!! Now all they have to do is clean up the spill in the gulf and on the beaches. We got the flow stopped so that should speed up the cleaning efforts.
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Quoting jrweatherman:


Then you are the worst forecaster on this blog....


OK OK lets not throw jeff under the bus.
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Quoting DestinJeff:



squirrel-casting??
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560. MTWX
Quoting DestinJeff:



As I wipe the Mt Dew off of my computer monitor!! LOL
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Quoting Patrap:
The VALVES have stopped the Oil flow.

FLASH TRAFFIC

FANTASTIC NEWS YEAH :o)
Member Since: August 25, 2009 Posts: 20 Comments: 6785
556. xcool
.IM KEEP EYE ON SW CAB & NHC 10% .KOOL
Member Since: September 26, 2009 Posts: 2 Comments: 15705
Quoting StormW:
Dry low?




sounds like chinese take out,lol....
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553. MTWX
Quoting StormW:


Yuck!

Where are you at?

Columbus, MS.. We are under an Excessive Heat Warning until 7 pm!
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Looks like They stopped the leak for now!!!
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Live feeds from the Gulf of Mexico ROVs
Member Since: July 3, 2005 Posts: 432 Comments: 132008
550. HadesGodWyvern (Mod)
Here is the latest Tropical Cyclone Bulletin issued by the Hong Kong Observatory.

The Standby Signal, No. 1 is in force.

This means that a tropical cyclone now centered within about 800 kilometers of Hong Kong may affect us.

At 3 a.m., Severe Tropical Storm Conson was estimated to be about 650 kilometers south-southwest of Hong Kong near 16.8N 111.9E and is forecast to move west-northwest at about 20 kilometers per hour across the northern part of the South China Sea in the general direction of Hainan Island.

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BREAKING NEWS

The BOP Stack VALVES have stopped the Oil flow.

The Choke Line valve is closed 100%

FLASH TRAFFIC


Live feeds from the Gulf of Mexico ROVs
Member Since: July 3, 2005 Posts: 432 Comments: 132008

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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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