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

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

Share this Blog
4
+

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

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 576 - 526

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

Quoting louisianaboy444:


Basically here is the complex rules of thumb..if it stays really weak it will move NW to NNW somewhere along the Upper Tx/LA coast and be a rainmaker...if it gets stronger it will be steered more by the high pressure system and the way the high is now that means more west towards S Tx...but the models are staying at the same strength and bringing it further Northward now looking more at Central and Upper Tx which tells me the High could be sliding east and maybe more of a NW movement could be opening up
It hits upper Texas coast then majority of drought stricken Texas get No rain.
Member Since: Posts: Comments:

540. DocNDswamp


Hiya Doc,,Im sure you remember the 05 Cindy that sputtered then had a good 48 hr run to Cat-1 off the Yucatan.

Member Since: July 3, 2005 Posts: 426 Comments: 128654
anybody seeing that TWC going into storm alert mode?
Member Since: Posts: Comments:
Quoting LavosPhoenix:


try the latest chrome dev, I know its' renderer (webkit) doesn't have problems with the truncated blog width as it did earlier this month or last month.



Chrome/chromium never gives me problems.
Member Since: Posts: Comments:
Quoting druseljic:
Missed the TWO. What was the percentage for 90L?



its up too 100%
Member Since: Posts: Comments:
okay i can call it don now
Member Since: Posts: Comments:
Soon to be TD appears to be really trying to "wrap around" on the vis loops in addition to the comment below as to the sirrus starting to flow off to the W/NW........Might be very close to TS strength by this evening and really curious to see what wind speeds the HH folks find over the next hour or so; they could go right to Don and skip TD if they find a closed circulation and the right wind speeds.
Member Since: Posts: Comments:
Quoting jasonweatherman2011:



are you talking about this map
yea thats it. whats going on with the africa wave?
Member Since: Posts: Comments:
556. j2008
Quoting alfabob:
I think maybe there should be a TS warning for the coast

They will have to if they find a TD or TS, which they should.
Member Since: December 19, 2008 Posts: 1 Comments: 224
I have the center around 21.9N/87.2W
Member Since: Posts: Comments:
553. SLU
Emily?

http://raleighwx.americanwx.com/models/euro/12zeu rotropical850mbVortSLP072.gif
Member Since: Posts: Comments:
Quoting druseljic:
Missed the TWO. What was the percentage for 90L?


Near 100%
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Missed the TWO. What was the percentage for 90L?
Member Since: Posts: Comments:
Quoting alfabob:
Think it just became stacked.
WOW its really blowing up!
Member Since: September 18, 2010 Posts: 0 Comments: 5234
Quoting RitaEvac:
Dang it, LA is hogging up all the rain..



Literally right on the border...wow
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Dang it, LA is hogging up all the rain..

Member Since: July 14, 2008 Posts: 1 Comments: 9630
Quoting Tazmanian:




you guys need firefox



Link


try the latest chrome dev, I know its' renderer (webkit) doesn't have problems with the truncated blog width as it did earlier this month or last month.
Member Since: Posts: Comments:
Product: Air Force Tropical RECCO Message (URNT11 KNHC)
Transmitted: 27th day of the month at 18:28Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Mission Purpose: Investigate third suspect area (flight in the North Atlantic basin)
Mission Number: 1
Observation Number: 04

Mandatory Data...

Observation Time: Wednesday, 18:24Z
Radar Capability: Yes
Aircraft Altitude: Below 10,000 meters
Coordinates: 23.3N 89.0W
Location: 464 miles (747 km) between the WSW and W (259°) from Key West, FL, USA.
Turbulence: None
Conditions Along Flight Route: In the clear
Pressure Altitude: 300 meters
Flight Level Wind: 5 knots (~ 5.8 mph) (Bearing was unavailable.)
- The above is a spot wind.
- Winds were obtained using doppler radar or inertial systems.
Flight Level Temperature: 25°C
Flight Level Dew Point: 14°C
Weather (within 30 nautical miles): Broken clouds (5/8 to 7/8 cloud coverage)
Mean Sea Level Pressure (MSLP): 1011 mb (extrapolated)

Optional Data...

Estimated Surface Wind: From 60° at 10 knots (From the ENE at ~ 11.5 mph)

Remarks Section...

Surface Wind Speed (likely by SFMR): 10 knots (~ 11.5mph)
Member Since: Posts: Comments:
The Browser Wars...

That said (or linked), NotCircumventing has a point, not everyone gets to use their browser of choice.

(Guess who is headed towards the coast tomorrow, and might get to ride out a TS/Cat 1 in a motel room? *sigh* Oh Don, I don't even know you and I already think we should break up.)
Member Since: Posts: Comments:
Quoting jasonweatherman2011:



are you talking about this map


ok...the blob of the carolinas...is that a NEW system or is the what 90L is going to become turning into a sweeper after a recurve or is it the rain we currently have plz...
Member Since: Posts: Comments:
The model may be way out in left field on 90L's future but based on GFS analysis / forecast to this point, I'll be curious to see if the organization we've seen since yesterday, especially today and into tomorrow is the best it gets... or further consolidates.

It's certainly a head-scratcher of a system and if recon confirms a closed LLC, I'd bet the NHC will be mentioning a high degree of uncertainty in their forecast discussions.
Member Since: Posts: Comments:
For now, 90L appears to have a valid LLC since there's NE WNDS being reported on the current HH path.

Yet... the WND field is quite small, given that it should be approaching the possible LLC fix in 15 to 20 or so.
Member Since: Posts: Comments:
Not much longer till recon now, eh
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Product: Air Force Tropical RECCO Message (URNT11 KNHC)
Transmitted: 27th day of the month at 18:24Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Mission Purpose: Investigate third suspect area (flight in the North Atlantic basin)
Mission Number: 1
Observation Number: 03

Mandatory Data...

Observation Time: Wednesday, 18:18Z
Radar Capability: Yes
Aircraft Altitude: Below 10,000 meters
Coordinates: 23.5N 89.2W
Location: 451 miles (726 km) to the S (173°) from New Orleans, LA, USA.
Turbulence: None
Conditions Along Flight Route: In the clear
Pressure Altitude: 300 meters
Flight Level Wind: 5 knots (~ 5.8 mph) (Bearing was unavailable.)
- The above is a spot wind.
- Winds were obtained using doppler radar or inertial systems.
Flight Level Temperature: 25°C
Flight Level Dew Point: Not available, probably because the dew point hygrometer was not working.
Weather (within 30 nautical miles): Broken clouds (5/8 to 7/8 cloud coverage)
Mean Sea Level Pressure (MSLP): 1012 mb (extrapolated)

Optional Data...

Estimated Surface Wind Direction: Bearing was unavailable.
Estimated Surface Wind Speed: 5 knots (~ 5.8 mph)
Member Since: Posts: Comments:
Quoting stormpetrol:


yep chrome, firefox or even safari.




firefox is the best lol
Member Since: Posts: Comments:
Quoting NotCircumventing:
Fact is that some people are constrained to using IE ...

just keep this in mind, that's all.


That's true too!
Member Since: Posts: Comments:
Quoting sarahjola:
will we know what direction 90l is moving for sure with recon? right now i don't see it making forward movement at all. i mean is it going wnw, w, nw, or what?


Basically here is the complex rules of thumb..if it stays really weak it will move NW to NNW somewhere along the Upper Tx/LA coast and be a rainmaker...if it gets stronger it will be steered more by the high pressure system and the way the high is now that means more west towards S Tx...but the models are staying at the same strength and bringing it further Northward now looking more at Central and Upper Tx which tells me the High could be sliding east and maybe more of a NW movement could be opening up
Member Since: Posts: Comments:
Quoting Tazmanian:




you guys need firefox



Link


yep chrome, firefox or even safari.
Member Since: Posts: Comments:
Quoting hurricanehunter27:
What OS do you guys think i should get Latest version of linux or snow leopard?


Or how about lion? ;)

Recon plane at operational altitude approaching from the NW.
Member Since: October 17, 2010 Posts: 0 Comments: 1267
Time: 18:17:30Z
Coordinates: 23.5667N 89.3W
Acft. Static Air Press: 962.9 mb (~ 28.43 inHg)
Acft. Geopotential Hgt: 441 meters (~ 1,447 feet)
Extrap. Sfc. Press: -
D-value: -
Flt. Lvl. Wind (30s): From 53° at 7 knots (From the NE at ~ 8.0 mph)
Air Temp: 24.1°C* (~ 75.4°F*)
Dew Pt: -*
Peak (10s) Flt. Lvl. Wind: 7 knots (~ 8.0 mph)
SFMR Peak (10s) Sfc. Wind: -
SFMR Rain Rate: -

Aircraft low and getting closer
Member Since: Posts: Comments:
476... Thanks. I'm on the upper texas coast and could use the rain. I do remember though going to bed with Humberto supposedley only making landfall as a 55-60 mph TS and waking up to a hurricane.
Member Since: Posts: Comments:

Viewing: 576 - 526

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40Blog Index

Top of Page

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.