Drought continues; Yellowstone fires could become more frequent; 90L set to develop

By: Dr. Jeff Masters , 3:58 PM GMT on July 27, 2011

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Southern Drought Continues

Temperatures continue to soar into triple digits in the Southern Plains this week, and are expected to remain well above average for at least the next month. High air temperatures and low humidity (because of the low soil moisture) will continue to maintain drought conditions in the South unless we see some Gulf-landfalling tropical cyclones—a good remedy for a such an extreme drought.

This year's drought in the South is unprecedented by many definitions. Last year at this time, 0% of the contiguous U.S. was in exceptional drought. Last week, the exceptional drought region covered 11.96%. The area of contiguous U.S. in exceptional drought conditions has never been this high since the Drought Monitor record started in 2000. The highest it had been before June of this year was 7.85% in August of 2002.


Figure 1. Temperature anomaly (difference from average) in degrees Celsius for the period July 1 through July 25 (top) and soil moisture anomaly in millimeters (bottom) on July 25 (from the Climate Prediction Center).

In late June, the U.S. Department of Agriculture designated 213 counties in Texas (84% of the state) as primary natural disaster areas. As I mentioned yesterday, the Texas drought and wildfires are one of the nine billion-dollar disasters of 2011 so far. The National Climatic Data Center estimated that this event had cost up to $3 billion as of June 16. This number is surely rising every day that the South doesn't see rain.

New study concludes Yellowstone wildfires could become more frequent

In a study published this week by the Proceedings of the National Academy of Sciences, researchers have concluded that global warming could have a serious impact on the severity and frequency of wildfires in the Yellowstone region (an area where the states of Montana, Idaho, and Wyoming come together). Historically in this region, fewer than 5% of wildfire occurrences account for 95% of the total area burned. But in a global warming scenario, they found that fire activity could become more severe and more frequent, causing the ecosystem to change dramatically.

Using climate conditions and historical fire data from 1972 to 1999, it was possible to link certain environmental thresholds (temperature, humidity, etc) to past wildfire events. Then by employing the output of various climate models, fire frequency can be forecast well into the future. Figure 2 illustrates the result from one of the climate models they used in the study, and the upward trend of fire activity over the next 100 years. In 1988, a particularly hot and dry year, 36% of the park burned. The study uses this year as a baseline to compare future events.


Figure 2. Figure 2B from the manuscript. Observed burn area (blue line) median of predicted area burned (black dotted line), and ranges (light and dark orange) aggregated over the Yellowstone area defined by the study by Westerling et al. (Source).

What was once a low-probability event could become a high-probability event by mid-century. Fires that have only happened every 100 to 300 years in the past could now be occurring every 30 years in the future. The results of this research has implications for sub-alpine forests across the globe. Warming temperatures and decreasing humidity will lead to more wildfires, and will cost billions of dollars to fight them, if we choose to do so.

Invest 90L

90L has moved west overnight and looks ripe to develop today. While the upper level circulation (500 mb) is very much displaced, the lower level circulation looks strong and coherent through the system's mid-levels (850 and 700 mb). Thunderstorm activity continues to organize, and it appears that a surface circulation is developing. Moisture remains high in the system (around 4.5 g/kg specific humidity) and wind shear should be somewhat favorable as it crosses through the Gulf of Mexico. In terms of track, the statistical models have generally been favoring a Brownsville landfall scenario, but the dynamical models have been inching north over the past day or so. The HWRF is in line with the ECMWF deterministic today, with landfall near Corpus Christi.



The Hurricane Hunters have a mission scheduled for 18Z today (2pm EDT) to investigate whether or not 90L has a closed surface circulation. If it does, given the amount of organized convection and moderate wind speeds (around 34 mph in the latest invest update), the Hurricane Center will probably call this system at least Tropical Depression Four.

If 90L develops this afternoon, I will have another update to look at track and intensity forecasts.

Angela

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668. ToddAndrews1

Watch out for the guys with the short haircuts, grey suits and extra shiny shoes.
Member Since: September 9, 2007 Posts: 36 Comments: 4687
Quoting alfabob:
I'm going to stab this Todd guy in the face if they don't stop it soon.


hit the report ! and then the ignore...he will be added to your list and you wont have to see his posts...hopefully he will be booted asap
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722. beell
Quoting MrstormX:


It's tiny, so i'm not surprised at this point.


For sure. Might end up being Mesoscale Convective Vortex #4
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amazing when you hit that ignore button,all the free space that shows up. What a wonderful button.
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RECON time
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Quoting Orcasystems:

Sorry to hear that.



????i could not under stan what you where saying any ways whats get back too 90L huh?
Member Since: May 21, 2006 Posts: 5091 Comments: 115239
Todd Andrews: I realize that you're new here. It's in bad form to call people names and post their personal information in this community. Please stop. If you don't stop, I will report you.
Thanks.
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Wonder what's taking admin so long to yank this moron?
Member Since: Posts: Comments:
Quoting Seawall:


I've got the fans out, trying to push some of that LA rain West into SE TX.


we still want it
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Quoting Gearsts:
And now you are quoting him:/ Please stop and deleted your coments and just ignore the user



i said i would stop lol whats move on too 90L plzs
Member Since: May 21, 2006 Posts: 5091 Comments: 115239
Quoting alfabob:
I'm going to stab this Todd guy in the face if they don't stop it soon.

Report, ignore, move on. Problem solved.
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Quoting nigel20:
The tropical wave at 30 W should be watched for future development.
I will. I hope dry air kills it.
Member Since: September 27, 2007 Posts: 1 Comments: 21416
Quoting Tazmanian:




well do could t help it lol

Sorry to hear that.
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Quoting Seawall:


I've got the fans out, trying to push some of that LA rain West into SE TX.
Hey, thanks, we will be so grateful if you succeed!
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Quoting Tazmanian:




you been reported
And now you are quoting him:/ Please stop and deleted your coments and just ignore the user
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Quoting beell:
Looks pretty weak based on recon so far. Not much of a pressure gradient.


It's tiny, so i'm not surprised at this point.
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Dislike, report, ignore....move on. Don't give him the time of day by quoting or mentioning it. As far as I'm concerned if you're quoting him you're almost just as guilty.

Recon should have a center fix in the next 10-15 minutes.
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Quoting Tazmanian:




LOL


Watch out! At this rate he is going to make a run for your high comment mark in a day or two!
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Quoting nrtiwlnvragn:
UK MET Office


GLOBAL MODEL DATA TIME 12UTC 27.07.2011



TROPICAL STORM DEVELOPED IN THE MODEL ANALYSIS AT POSITION : 21.7N 86.7W



VERIFYING TIME POSITION STRENGTH TENDENCY

-------------- -------- -------- --------

12UTC 27.07.2011 21.7N 86.7W WEAK

00UTC 28.07.2011 22.4N 87.7W WEAK LITTLE CHANGE

12UTC 28.07.2011 22.9N 90.0W WEAK LITTLE CHANGE

00UTC 29.07.2011 24.3N 92.5W WEAK LITTLE CHANGE

12UTC 29.07.2011 25.7N 94.6W WEAK LITTLE CHANGE

00UTC 30.07.2011 26.1N 96.8W WEAK WEAKENING SLIGHTLY

12UTC 30.07.2011 BELOW TROPICAL STORM STRENGTH






Gotta love the UKMET
Member Since: May 27, 2009 Posts: 0 Comments: 4438
The tropical wave at 30 W should be watched for future development.
Member Since: November 6, 2010 Posts: 11 Comments: 8144

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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.