Colin arrives; extreme heat records fall for Ukraine and 5 U.S. cities

By: Dr. Jeff Masters , 12:16 PM GMT on August 03, 2010

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Tropical Storm Colin has made its debut over the Atlantic, but does not appear to be a threat to any land areas over the next five days. Satellite imagery shows that Colin is intensifying, as both the intensity and areal extent of heavy thunderstorms has increased over the past few hours. A respectable low-level spiral band is developing to the north of the center, and upper-level outflow is beginning to appear on all sides of the storm. Colin is a very small storm, and its tropical storm force winds extend out just 30 miles from the center. Colin passed about 50 miles south of Buoy 41041 early this morning, and generated top sustained winds of 27 mph at the buoy. There is some dry air associated with the Saharan Air Layer (SAL) to the northwest of Colin, but this dry air is not getting entrained into Colin at present. Wind shear is a low 5 - 10 knots and sea surface temperatures are a very warm 28 - 29°C, so continued development is likely today. The main negative for development appears to be the storm's small size, which makes it vulnerable to modest increases in wind shear or dry air entrainment. The first flight of the Hurricane Hunters into Colin is scheduled for Wednesday morning.


Figure 1. Morning satellite image of Tropical Storm Colin.

Forecast for Colin
The latest 6Z (2am EDT) models are fairly unified taking Colin to the west-northwest at 20 - 25 mph for the next three days. This would bring squalls from the storm's outer rainbands to the northern Lesser Antilles Islands, such as Antigua and Barbuda, by Wednesday afternoon. The center of Colin should pass to the northeast of the islands, and the storm is small enough that the islands are unlikely to experience tropical storm force winds. As Colin makes its closest approach to the Lesser Antilles on Wednesday night, the storm will begin to encounter strong upper-level westerly winds associated with the counter-clockwise flow of air around an upper-level low pressure system centered between Bermuda and Puerto Rico. The latest SHIPS model forecast predicts that these winds will cause wind shear to rise to the moderate level, 10 - 20 knots, by Wednesday morning, and to the high level, 20 - 30 knots, by Thursday. There is considerable dry air associated with the upper level low that should cause problems for Colin, as well. The high wind shear and dry air should weaken Colin. NHC is giving Colin a 25% chance of attaining hurricane status this week.

A trough of low pressure is expected to move off the U.S. East Coast on Friday, and this trough will pull Colin to the northwest and cause it to slow down on Wednesday. By Friday, Colin will be moving at half of its current speed. It is unclear if the trough of low pressure will be strong enough to fully recurve Colin out to sea late this week. Some of the models predict Colin will not recurve out to sea, and that high pressure will build back in this weekend, forcing Colin towards the U.S. East Coast. A second trough of low pressure is predicted to move off the U.S. East Coast next Monday, so Colin will have a second opportunity to recurve out to sea then. It is possible that Colin could make landfall along the U.S. East Coast or in the Canadian Maritime provinces 7 - 10 days from now, though it is still too early to assess the risk of this happening, nor how strong Colin might be.

Ukraine ties its record for hottest temperature in history
On August 1, Ukraine tied its record for hottest temperature in its history when the mercury hit 41.3°C (106.3°F) at Lukhansk. The Ukraine also reached 41.3°C on July 20 and 21, 2007, at Voznesensk. Sixteen of 225 nations on Earth have set extreme highest temperature in history records this year, the most of any year. The year 2007 is in second place, with fifteen such records.

Five major U.S. cities record their warmest month in history during July
July 2010 was the warmest month in history for five U.S. cities:

Las Vegas, NV: 96.2°F (old record: 95.3°F, July 2005).
Atlantic City, NJ: 79.8°F (old record: 78.7°F, July 1983)
Washington, D.C.: 83.1°F (tied with July 1993)
Baltimore, MD: 81.5°F (tied with July 1995)
Trenton, NJ: 80.5°F (tied with July 1955)

Also, in June, Miami, FL recorded its warmest month in history: 85.6°F (old record: 85.4°F in June 1998.)

Commentary
None of the 303 major U.S. cities listed in the records section of Chris Burt's book Extreme Weather has set a coldest month in history record since 1994 (these 303 cites were selected to represent a broad spectrum of U.S. climate zones, are not all big cities, have a good range of elevations, and in most cases have data going back to the 1880s.) There were just three such records (1% of the 303 major U.S. cities) set in the past twenty years, 1991 - 2010. In contrast, 97 out of 303 major U.S. cities (32%) set records for their warmest month in history during the past twenty years. It is much harder to set a coldest month in history record than a coldest day in history record in a warming climate, since it requires cold for an extended period of time--not just a sudden extreme cold snap.

Are the pattern of U.S. temperature records due to the Urban Heat Island effect?
Is the huge disparity between extreme heat records and extreme cold records in the U.S. due to global warming, or the Urban Heat Island effect? The Urban Heat Island (UHI) effect occurs when development of former natural areas into pavement and buildings allows more heat to be trapped in cities, particularly at night. During the day, the UHI effect often leads to a slight cooling, since it can increase the amount of turbulence, allowing cooler air to get mixed down to the surface. For example, Moreno-Garcia (1994) found that Barcelona, Spain was 0.2°C cooler for daily maxima and 2.9°C warmer for minima than a nearby rural station.

However, temperature records are typically taken in parks and airports removed from the main heat-trapping areas of cities, and are not as strongly affected as one might expect. There are several reasons for this. One is that when tall buildings are present, they tend to block the view to the sky, meaning that not as much heat can escape upwards. In addition, the presence of moist vegetation keeps the atmosphere moister in park-like areas (which include the grassy fields near airports where temperature measurements are taken). This extra moisture helps cool the atmosphere on a local scale of tens of meters, due to latent heat effects (the energy required to convert liquid water to water vapor). Peterson (2003) found that "Contrary to generally accepted wisdom, no statistically significant impact of urbanization could be found in annual temperatures." The study used satellite-based night-light detection to identify urban areas. Recent research by Spronken-Smith and Oke (1998) concluded that there was a marked park cool island effect within the Urban Heat Island. They found that parks in typical cities in the U.S. have temperatures 1 - 2°C cooler than the surrounding city--and sometimes more than 5°C cooler. While the Urban Heat Island effect probably has contributed to some of the reduction in record low temperatures in the U.S. in the past decade, research by Parker (2004, 2006) and Peterson (2003) theorizes that Urban Heat Island effect is a factor ten or more less important than rising temperatures due to global warming.

Chris Burt wrote me yesterday about Las Vegas' all-time warmest month record set in July. He noted that none of the sites nearby Las Vegas' McCarran Airport (where the official obs are kept) came close to setting a warmest month in history record. McCarran Airport has set new warmest month in history records in 2003, 2005, and now 2010. These two facts make us suspect that in the case of Las Vegas, an urban heat island effect may be contributing to the spate of recent warmest month in history records there. The heat records for Atlantic City, Washington D.C., Baltimore, and Trenton do not appear to have as much of a UHI influence, since record highs were set over such a large area of the mid-Atlantic in July.

Is the Urban Heat Island effect partially responsible for global warming?
Global warming is affecting the entire Earth, including rural areas far from cities, and the 70% of the world covered by ocean. Thus, the Urban Heat Island effect--if not corrected for--can cause only a small impact on the global temperature figures. Since the Urban Heat Island is corrected for, the impact on the observed global warming signal should be negligible. For instance, NASA uses satellite-derived night light observations to classify stations as rural and urban and corrects the urban stations so that they match the trends from the rural stations before gridding the data. Other techniques (such as correcting for population growth) have also been used. Despite these corrections, and the fact that the Urban Heat Island effect impacts only a relatively small portion of the globe, global warming skeptics have persistently used the Urban Heat Island effect to attack the validity of global warming. There are no published peer-reviewed scientific studies that support these attacks.

References
Parker, D.E., 2004, "Large-Scale Warming is not Urban", Nature 432, 290, doi:10.1038/432290a, 2004.

Parker, D.E., 2006, "A Demonstration that Large-Scale Warming is not Urban", J. Climate 19, pp2882-2986, 2006.

Peterson, T.C., "Assessment of urban versus rural in situ surface temperatures in the contiguous United States: No difference found", Journal of Climate, 16, 2941-2959, 2003.

Spronken-Smith, R. A., and T. R. Oke, 1998: "The thermal regime of urban parks in two cities with different summer climates. Int. J. Remote Sens., 19, 20852104.

The surface temperature record and the urban heat island, realclimate.org post, 2004.

Next update
I have a series of meetings today that will probably keep me from making another post, and keep me from doing my weekly Internet radio show, Hurricane Haven. I'll be back Wednesday morning, at the latest, with a new post.

Jeff Masters

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1975. Skyepony (Mod)
Quoting Snowlover123:


What does everyone think of the Caribbean disturbance, since 04L won't regenerate according to the NHC?


The NHC final (for now) forecast on 04L Colin has it regenerating in 5 days..
Member Since: Posts: Comments:
1974. bappit
Similar pic for the Caribbean wave. You can see how much better organized Colin is.

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1973. breald
Quoting KoritheMan:


I thought a lot of them still came around. Maybe it's me.


I might be missing them if they do come around.
Member Since: May 28, 2008 Posts: 38 Comments: 5303
Quoting Patrap:
Presslord is Chairman of Portlight.org,..

The latest on our combined efforts is now seen in the Portlight Featured Blog here.


I miss Press' witty banter. Not only is he knowledgeable he is entertaining!
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Thx Storm...
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1970. Patrap
Quoting bohonkweatherman:
Good Evening Patrap and StormW, You guys add so much to this Blog and you are appreciated just like the others like Levi and MH09 etc.


Evening..
The sharing is what the wunderground is all about.

So all that post contribute,..and thats a good thing always.
Member Since: Posts: Comments:
1969. Patrap
Presslord is Chairman of Portlight.org,..

The latest on our combined efforts is now seen in the Portlight Featured Blog here.
Member Since: Posts: Comments:
Quoting StormW:
REMNANT LOW COLIN UPDATE AUGUST 03, 2010 ISSUED 8:25 P.M.


To echo others: nice update. Succinct and to the point...
Member Since: November 8, 2009 Posts: 4 Comments: 13568
Quoting breald:


That's right he was in charge of the portlight charity. I can't think of anyone else I use to see here last year.


I thought a lot of them still came around. Maybe it's me.
Member Since: Posts: Comments:
1965. bappit
Here's the MIMIC pic off the CIMSS site for Colin.



The arrows are vectors of apparent motion as the camera moves along with the system. The center appears to be near 16.1 N, 53.5 W. Just an estimate based on the MIMIC picture. Colin is moving so fast it has gotten ahead of the center of the frame.

There still is a complete/closed circulation of air (the air is following a path around the center), but to a viewer on the ground the addition of the forward speed may make the circulation look open.
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Thanks Koritheman.
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Good Evening Patrap and StormW, You guys add so much to this Blog and you are appreciated just like the others like Levi and MH09 etc.
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Storm....do any of the models pick up on the disturbance in the SE Carib??
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1960. guygee
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 215 Issued at 2200Z on 03 Aug 2010
[...]
IIA. Geophysical Activity Summary 02/2100Z to 03/2100Z:
Geomagnetic field activity was at mostly quiet levels until late in the period. Activity increased to unsettled to active levels following a sudden geomagnetic impulse (SI) at 03/1741Z (21 nT, as measured by the Boulder USGS magnetometer). The SI was preceded by the arrival of an interplanetary shock at the ACE spacecraft at 03/1656Z. Both effects were due to the arrival of a CME associated with the long-duration C3 flare on 01 August. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period.

IIB. Geophysical Activity Forecast: Geomagnetic field activity is expected to be at unsettled to minor storm levels on day 1 (04 August) as the current CME passage continues. Activity is forecast to increase to active to minor storm levels with a chance for major storm levels on day 2 (05 August) due to the arrival of the halo-CME observed on 01 August (associated with a large filament disappearance). Activity is expected to decrease to unsettled to active levels on day 3 (06 August) as CME effects subside.[...]
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Great update Storm.
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Quoting mrsalagranny:
Can someone please post me a link for the satellite of the carribean wave?TIA


Link
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1956. leu2500
re 1911: That must be why it's so blazing hot. I know it's Aug in Alabama & we're not too far from the start of the dog days, but the weeks of mid to upper 90s and humidity (since June!) have definitely gotten old.

Do any of the models show it moving out any time soon?
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Quoting KEEPEROFTHEGATE:
UPDATE: Northern Lights are being sighted now in Europe. Jesper Grønne sends this picture from Denmark (latitude +56 degrees):


Rob Stammes sends this report from Laukvik, Lofoten, Norway: "At 17.40 UT, electrical currents began to flow throgh the ground outside my laboratory: data. This indicated the arrrival of the CME. Three hours later a geomagnetic storm is active, strong enough for auroras."

Red auroras are being sighted over Germany


I know they were saying this would be a northern event. How far south do you think it could potentially go?
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what do the mode runs show
Member Since: May 21, 2006 Posts: 5091 Comments: 115244
1953. breald
Quoting KoritheMan:


I still see SJ from time to time. presslord said he was permanently withdrawing on his main handle, and would only be posting his "Portlight" handle to update the folks here on the organization's efforts during the aftermath of a disaster.


That's right he was in charge of the portlight charity. I can't think of anyone else I use to see here last year.
Member Since: May 28, 2008 Posts: 38 Comments: 5303
Quoting catastropheadjuster:


StormJunkie's around a little I think he had a baby or going to school. I think. Presslord is with Portlight. I haven't seen 456 in a few days. Storm was on earlier,and drakeon,levi. but they left it got a little much with the GW crap.
Sheri


It's really sad when the childishness on here runs off some of the best. Most of the time it's the adults, not the kids that are most responsible. I don't blame the valued for not wanting to stick around. They can take their skills and go anywhere. Unfortunately, for those of us far less skilled, it is a loss.
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1950. Patrap
All NOAA Tropical Floater Imagery

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1949. Patrap
The shoo-shoo's of the Tropical Atlantic continues..

More time to get ready for when a Buzz Saw develops and threatens the curtains or worse.

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Thank you StormW!

Quoting StormW:
REMNANT LOW COLIN UPDATE AUGUST 03, 2010 ISSUED 8:25 P.M.
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Can someone please post me a link for the satellite of the carribean wave?TIA
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1946. KYDan
Quoting IKE:


They do have a "weed eater". It's called your "ignore user" option. It's helps.


There is another option that many blogs/message boards use, and that is a pay for play section. The free blog/message board remains open to all, but if you want to play in a serious manner you pony up some money for every handle you register.

I am a member and moderator of a sports message board and we did this about 6 years ago. It is amazing how much more civil and on topic the discussion is on the pay for play board versus the come one come all board.

Just sharing a thought.
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1944. Patrap
NOAA: Global Warming "undeniable"


Global warning is "undeniable" says a new report published by the National Oceanic and Atmospheric Administration (NOAA), which looked at 10 climate indicators and concluded they "all tell the same story."

"People have spent thousands of years building society for one climate and now a new one is being created - one that's warmer and more extreme," the NOAA report states.

The 10 indicators included shrinking glaciers, melting spring snow cover in the Northern Hemisphere, declining sea-ice in the Arctic, sea-surface temperature, higher air temperature over land, air temperature over oceans, humidity and temperature in the troposphere, and ocean heat.

The NOAA report was released during a week when, faced with the specter of a filibuster, U.S. Senate leaders abandoned efforts to pass a comprehensive clean energy-climate bill.

Climate reform legislation did pass the U.S. House of Representatives last summer, against fierce opposition from Big Oil, the coal industry and the U.S. Chamber of Commerce.

In the Senate, however, it faced opposition from Republicans and Democrats from coal and oiul producing states.

The NOAA report was compiled by investigators from 48 different countries. It noted that each of the preceding three decades was hotter than the decade before.

The 1980's was the hottest decade on record - prompting initial alarm about global warming - only to find temperatures increasing every year during the 1990's. The warming continued into the 21st Century.

Temperatures increased between 2000 and 2009, with the first half of 2010 the warmest on record.

"Glaciers and sea ice are melting, heavy rainfall is intensifying and heat waves are more common . . . There is now evidence that more than 90 percent of warming over the last 50 years has gone into our oceans," said Deke Arndt, manager of the NOAA Climate
Monitoring Branch and co-editor of the new report.

Extreme weather conditions have been part of the trend.

Pakistan has just experienced its most intense Monsoon rains on record. Last year, floods in Brazil left 376,000 people homeless. Record heat waves led to furious fires last year in Australia, and this year in central Russia.

In reaching their conclusion, scientists used data from weather satellites, weather balloons, weather stations, buoys and ships.
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
UPDATE: Northern Lights are being sighted now in Europe. Jesper Grønne sends this picture from Denmark (latitude +56 degrees):


Rob Stammes sends this report from Laukvik, Lofoten, Norway: "At 17.40 UT, electrical currents began to flow throgh the ground outside my laboratory: data. This indicated the arrrival of the CME. Three hours later a geomagnetic storm is active, strong enough for auroras."

Red auroras are being sighted over Germany


Very intense--look at the deep reds over Europe--but not a lot of southward penetration...yet:



Link
Member Since: November 8, 2009 Posts: 4 Comments: 13568
There are a couple AOI and waves are lined up over Africa, enjoy any slow time we get, things could change pretty fast just like they did for Colin.
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1941. SLU
Quoting xcool:
Time to Tone Down Hurricane Season Prognostications?
August 3, 2010 · 0 comments

With a third of the Atlantic hurricane season over and just three storms named (albeit accompanied by two tropical depressions), should hurricane season prognosticators consider backing down from their early season forecasts of a wild season? And we’re not just talking about one or two Punxatawny Phils here — this year realized eight separate forecasts of named storms and hurricanes for the six-month season, which began June 1. Predictions of the number of named storms ranged from 17 to a lofty 23 — far above the average of 11 named storms realized over the last 60 years.






real meat of hurricane season is from mid August through mid October, when about 90% of a season’s storms form. Based on the May and June forecasts, that would equate to about 15-21 tropical storms and hurricanes — still a substantially busy season. But the chatter has begun on the blogs (2nd topic on this page) and in the online and mainstream news that this year will not be like 2005. By this point in that season the Atlantic had already seen eight named storms, including two major hurricanes. The 2005 season went on to realize 27 named storms, including Category 5 Hurricanes Katrina, Rita, and Wilma, and one unnamed storm added to the tally in the post-season.

So what drove the early season forecasts? And why might they need to be lowered? As in 2005, sea surface temperatures (SSTs) across the Atlantic basin have been well above average since spring. In fact, record warm SSTs have dominated the main tropical cyclone development region—from 10°N to 20°N between the coast of Africa and Central America (20°W – 80°W)—for five consecutive months (see the 2nd topic entry on this page). Combine that with lower-than-normal surface pressure basin wide and the fact that El Niño was not ending but appeared poised to transition to La Niña conditions (which it did) in the tropical Pacific, both of which are factors that can lead to more than the usual number of storms, and forecasters had almost no choice but to set their sights rather high. Conditions appeared very favorable for a quick start to a long and busy season, not unlike 2005.

Problem is, that hasn’t happened. The tropical cyclones that have developed this year have struggled. Despite all the favorable features, it appears dry air and more importantly strong wind shear across the Caribbean and Gulf of Mexico in June and July have kept storms in check. Typically, the atmosphere over the Atlantic Basin moistens significantly starting in August as the westward-moving Saharan dust outbreaks wane. And seasonal wind shear also becomes more conducive for storm development by August. Still, the next four months would need to see the pace of tropical storm and hurricane formation come fast and furious to realize the forecasts. It could happen: in 1995, 16 tropical storms and hurricanes, including five major hurricanes, formed one after another after another from the last days of July through the end of October, leaving just 10 days in the three-month period free of any storms. But that kind of hurricane history isn’t likely to repeat itself. Even 2005 had more storm-free days in the same portion of the season.

So what will forecasters do? Time will tell as two of the leading forecast teams—NOAA and the Colorado State University Tropical Meteorology Project, led by Phil Klotzbach and William Gray—update their forecasts this week. (Check these links for their updated forecasts: CSU (Aug. 4) and NOAA (Aug. 5).




Link


We still have all the ingredients for a dangerously active season.

Just imagine:

If Alex got to spend say 12 - 24 more hours over water, it could have exploded into a cat 4 or worse.

If TD #2 and several other invests which moved inland quickly got to stay over water longer ....

If Bonnie was properly positioned next to the upper low, then it would have been well ventilated and not sheared. It might not have remained a weak TS ....

If Colin didn't decouple and the TUTT was weaker and further away ....

If 92L and 95L were classified accordingly at peak strength ....


With La Nina, lower than normal pressures, record warm SSTs for months on end, well established wave train, etc etc etc .. You're going to struggle to find points to argue against a major season in 2010.

I see no reason for CSU to reduce their numbers tomorrow but I believe they will probably reduce the number of named storms by one or two but keep the hurricanes and major hurricanes as the same. The reason being that there's enough fuel out there for most of the systems which will eventually form, to develop into powerful systems once they don't run into land or the TUTT (if still present) or some unusual inhibiting factor.
Member Since: July 13, 2006 Posts: 13 Comments: 5262
Quoting breald:


Storm Junkie, Presslord they haven't been around either. I wonder what happened?


StormJunkie's around a little I think he had a baby or going to school. I think. Presslord is with Portlight. I haven't seen 456 in a few days. Storm was on earlier,and drakeon,levi. but they left it got a little much with the GW crap.
Sheri
Member Since: Posts: Comments:
Me thinks Taz either had the same icon idea and downloaded, or found my icons....either way, happy to share.

but Taz, I really think it is condition green right now....(lol, I am a dork)

Quoting Tazmanian:
look like they took care of JFV at last
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Quoting breald:


Storm Junkie, Presslord they haven't been around either. I wonder what happened?


Presslord only post under the Portlight handle now. Storm Junkie still post from time to time.
Member Since: Posts: Comments:
1937. Patrap
This in Dr. Masters entry.

And to be sure the posts that cover the entire entries topics, can and are welcomed.

If one cant handle the science of the Climate of the Earth,and the data presented from peer reviewed sources and conclusions,,that NOAA presents as well.

One can open their own collective entry here on the wunderground and present a view, personal or scientific voice..or post here as well.

That's what Freedom is.

Ukraine ties its record for hottest temperature in history
On August 1, Ukraine tied its record for hottest temperature in its history when the mercury hit 41.3C (106.3F) at Lukhansk. The Ukraine also reached 41.3C on July 20 and 21, 2007, at Voznesensk. Sixteen of 225 nations on Earth have set extreme highest temperature in history records this year, the most of any year. The year 2007 is in second place, with fifteen such records.

Five major U.S. cities record their warmest month in history during July
July 2010 was the warmest month in history for five U.S. cities:

Las Vegas, NV: 96.2F (old record: 95.3F, July 2005).
Atlantic City, NJ: 79.8F (old record: 78.7F, July 1983)
Washington, D.C.: 83.1F (tied with July 1993)
Baltimore, MD: 81.5F (tied with July 1995)
Trenton, NJ: 80.5F (tied with July 1955)

Also, in June, Miami, FL recorded its warmest month in history: 85.6F (old record: 85.4F in June 1998.)

Commentary
None of the 303 major U.S. cities listed in the records section of Chris Burt's book Extreme Weather has set a coldest month in history record since 1994 (these 303 cites were selected to represent a broad spectrum of U.S. climate zones, are not all big cities, have a good range of elevations, and in most cases have data going back to the 1880s.) There were just three such records (1% of the 303 major U.S. cities) set in the past twenty years, 1991 - 2010. In contrast, 97 out of 303 major U.S. cities (32%) set records for their warmest month in history during the past twenty years. It is much harder to set a coldest month in history record than a coldest day in history record in a warming climate, since it requires cold for an extended period of time--not just a sudden extreme cold snap.

Are the pattern of U.S. temperature records due to the Urban Heat Island effect?
Is the huge disparity between extreme heat records and extreme cold records in the U.S. due to global warming, or the Urban Heat Island effect? The Urban Heat Island (UHI) effect occurs when development of former natural areas into pavement and buildings allows more heat to be trapped in cities, particularly at night. During the day, the UHI effect often leads to a slight cooling, since it can increase the amount of turbulence, allowing cooler air to get mixed down to the surface. For example, Moreno-Garcia (1994) found that Barcelona, Spain was 0.2C cooler for daily maxima and 2.9C warmer for minima than a nearby rural station.

However, temperature records are typically taken in parks and airports removed from the main heat-trapping areas of cities, and are not as strongly affected as one might expect. There are several reasons for this. One is that when tall buildings are present, they tend to block the view to the sky, meaning that not as much heat can escape upwards. In addition, the presence of moist vegetation keeps the atmosphere moister in park-like areas (which include the grassy fields near airports where temperature measurements are taken). This extra moisture helps cool the atmosphere on a local scale of tens of meters, due to latent heat effects (the energy required to convert liquid water to water vapor). Peterson (2003) found that "Contrary to generally accepted wisdom, no statistically significant impact of urbanization could be found in annual temperatures." The study used satellite-based night-light detection to identify urban areas. Recent research by Spronken-Smith and Oke (1998) concluded that there was a marked park cool island effect within the Urban Heat Island. They found that parks in typical cities in the U.S. have temperatures 1 - 2C cooler than the surrounding city--and sometimes more than 5C cooler. While the Urban Heat Island effect probably has contributed to some of the reduction in record low temperatures in the U.S. in the past decade, research by Parker (2004, 2006) and Peterson (2003) theorizes that Urban Heat Island effect is a factor ten or more less important than rising temperatures due to global warming.

Chris Burt wrote me yesterday about Las Vegas' all-time warmest month record set in July. He noted that none of the sites nearby Las Vegas' McCarran Airport (where the official obs are kept) came close to setting a warmest month in history record. McCarran Airport has set new warmest month in history records in 2003, 2005, and now 2010. These two facts make us suspect that in the case of Las Vegas, an urban heat island effect may be contributing to the spate of recent warmest month in history records there. The heat records for Atlantic City, Washington D.C., Baltimore, and Trenton do not appear to have as much of a UHI influence, since record highs were set over such a large area of the mid-Atlantic in July.

Is the Urban Heat Island effect partially responsible for global warming?
Global warming is affecting the entire Earth, including rural areas far from cities, and the 70% of the world covered by ocean. Thus, the Urban Heat Island effect--if not corrected for--can cause only a small impact on the global temperature figures. Since the Urban Heat Island is corrected for, the impact on the observed global warming signal should be negligible. For instance, NASA uses satellite-derived night light observations to classify stations as rural and urban and corrects the urban stations so that they match the trends from the rural stations before gridding the data. Other techniques (such as correcting for population growth) have also been used. Despite these corrections, and the fact that the Urban Heat Island effect impacts only a relatively small portion of the globe, global warming skeptics have persistently used the Urban Heat Island effect to attack the validity of global warming. There are no published peer-reviewed scientific studies that support these attacks.

References
Parker, D.E., 2004, "Large-Scale Warming is not Urban", Nature 432, 290, doi:10.1038/432290a, 2004.

Parker, D.E., 2006, "A Demonstration that Large-Scale Warming is not Urban", J. Climate 19, pp2882-2986, 2006.

Peterson, T.C., "Assessment of urban versus rural in situ surface temperatures in the contiguous United States: No difference found", Journal of Climate, 16, 2941-2959, 2003.

Spronken-Smith, R. A., and T. R. Oke, 1998: "The thermal regime of urban parks in two cities with different summer climates. Int. J. Remote Sens., 19, 20852104.

The surface temperature record and the urban heat island, realclimate.org post, 2004.







Member Since: Posts: Comments:
Quoting breald:


Storm Junkie, Presslord they haven't been around either. I wonder what happened?


SJ was on earlier today. He is taking a heavy load of classes this summer, so no time to blog.
Member Since: September 23, 2005 Posts: 14 Comments: 11215
Quoting catastropheadjuster:


It is don't leave. Just start talking about the tropics there just trying to over load with that other crap. That's what they want.
sheri


Nah, I like to stick around for a few more minutes to see what's going on. :)
Quoting truecajun:
evening snow. i'm out too. i need some chocolate.


Evening! What type of choco? :)

What does everyone think of the Caribbean disturbance, since 04L won't regenerate according to the NHC?
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Quoting breald:


Storm Junkie, Presslord they haven't been around either. I wonder what happened?


I still see SJ from time to time. presslord said he was permanently withdrawing on his main handle, and would only be posting his "Portlight" handle to update the folks here on the organization's efforts during the aftermath of a disaster.
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Quoting IKE:


They do have a "weed eater". It's called your "ignore user" option. It's helps.


I know i just never really used it until the other day and it's pretty nice. But i never thought about it being like a weed eater, pretty cool.
Have a nice evening.
Sheri
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My goodness Aussie that high pressure is huge.You are right nothing will get close with that there.Wonder how long it will be there?
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Quoting CybrTeddy:
Quite a change in tune with the Caribbean disturbance. From unfavorable to favorable for gradual development.
It's looking pretty good now.
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KOTG, you should credit spaceweather.com for that info.
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1927. breald
Quoting catastropheadjuster:


Pat was on today. I don't think I've seen Tim (TS)I really miss seeing alot of them to, this place has changed alot just look at some of the crap that goes on know. I wish they had a weed eater to weed out some of these bloggers that cause trouble and just love to start a argument.
Sheri


Storm Junkie, Presslord they haven't been around either. I wonder what happened?
Member Since: May 28, 2008 Posts: 38 Comments: 5303
Quoting IKE:


They do have a "weed eater". It's called your "ignore user" option. It's helps.


I would like to echo this statement a thousand times over.
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evening snow. i'm out too. i need some chocolate.
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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.