The Northeast Heatwave

By: Dr. Jeff Masters , 9:08 AM GMT on July 07, 2010

Share this Blog
3
+

Hi, Dr. Rob Carver, filling in for Jeff while he's on vacation.

The most significant weather event in the US on July 6, 2010 didn't show up on any radar. The geostationary satellites didn't see it in their constant watch over the Earth's atmosphere. Instead, the tale of this event was told by the thermometers, because the heatwave in the Northeast was the most significant event for July 6, and it will likely be the most important weather story for July 7.

The heat wave covers Pennsylvania to Maine, but Tuesday's worst was centered over New York City. All six of the stations used by the New York NWS office for climate reports (Central Park, La Guardia, JFK, Islip, Bridgeport, and Newark) set or tied the daily high temperature record. Newark and Central Park both reached 103 degrees F.

How unusual is this heat wave?
Figures 1 and 2 show how warm the highs and lows are compared to 30 year averages. Unless you were at the Great Lakes, the Midwest and Northeast have highs well above normal, with 10-15+ degree F differences over the coastal cities of the Northeast. Using my gridded temperature data, the low for New York City was 6 degrees F above normal, which should happen 30% of the time (1.1 standard deviations away from normal). The high was roughly 20 degrees above normal, which should happen only 0.29% of the time (3.04 standard deviations away from normal). This is an unusually strong heat wave.

Why it's hot
Basically, it's because there is "the Bull of a high pressure ridge [over the NE US]" to quote the Mount Holly NWS office forecast discussion. The large ridge of high pressure is forcing air to slowly descend across the Northeast, preventing clouds from forming. Without no clouds and plenty of daylight, the Sun heats the ground which then heats the air.

When will it cool down?
That's an excellent question. A trough of low pressure off the coast will bring onshore winds to the Tri-State area and MA by Thursday, so they should cool down a bit. The southern part of the heat wave, DC and Philadelphia, will have to wait for a cold front to arrive from the Great Lakes sometime Saturday to get relief.

Population affected
As Figure 3 shows, heat advisories covered most of the urban areas of the northeastern US. By my calculations, over 32 million people were under a heat advisory. Different offices have different guidelines for heat advisories. The NWS office responsible for New York issues a heat advisory if the heat index will be above 95 deg. F for two or more days or if the index will be above 100 deg. F for any length of time.


Fig.1 Plot of the difference between maximum temperature (the high for the day) and average maximum temperature in degrees F for July 6.


Fig.2 Plot of the difference between minimum temperature (the low for the day) and average minimum temperature in degrees F for July 6.


Fig.3 Plot of the active heat advisories across the northeastern US for July 6.

Heatwave impacts
The predominant impact from heat waves is increased mortality. CDC estimates that over 8,000 people died during heat waves from 1979 to 2003. That's more than all of the deaths due to lightning, flooding, tornadoes, hurricanes, and earthquakes. The elderly, sick, poor, and very young face the worst of the effects of the heat. Wikipedia has an interesting article describing the Chicago Heat Wave of 1995, a modern heat wave with a large number of fatalities due to the heat.

Heatwave coping strategies
The Centers for Disease Control have some tips for dealing with the heat. In summary, drink plenty of water, spend time in air-conditioned buildings, and wear light-colored clothing.

Is this heat wave due to global warming?
Ah, the $64,000 question. In the absence of detailed analysis, it's hard to specify the exact cause for this heat wave, from a meteorological or climatological view point. However, events like this are consistent with research showing that heat waves are more likely with
global warming
. I like the metaphor of loaded dice, global warming is not specifically responsible for any heat wave, but it will make them happen more often.

Tropics
My thinking on Invest 96L is unchanged from this blog entry. In summary, I believe that 96L has a <50 % chance becoming a tropical cyclone before it makes landfall. If it does so, it will likely be near the coast when that happens. In any event though, the winds and waves it generates will likely disrupt oil spill recovery efforts. Also, I would expect a broad area of showers and 20+ mph winds will affect the Gulf coast somewhere from south Texas to Louisiana.

Next update
I'll have an update this afternoon to talk about the tropics.

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: 187 - 137

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 | 37Blog Index

Member Since: July 3, 2005 Posts: 428 Comments: 129844
I have been a watcher of this blog since 2004. I do not consider myself sufficient to talk about meteorological events. So I have the proverbial "dumb question". From all the reading I've done, the high pressure that has existed over the southeast (I'm a resident of Florida in Ft Pierce)is not good from the standpoint of recurving tropical storms or hurricanes away from the Southeast Florida coast. Right? But if I recall, if the Bermuda High is extended further east in the Atlantic, that would either help in turning them toward us or bringing them up towards Bermuda. Is my understanding correct?
Member Since: Posts: Comments:
Thanks Storm,,,more rain for Houston..
Member Since: Posts: Comments:
Quoting StormW:


Where to?

Navarre....a little slice of Heaven!
Member Since: Posts: Comments:
Freddy was a badass no doubt. I live next to the Naval Air Station. I was alot closer to IVAN than FREDDY and my personal experience was much worse with IVAN because of the proximity. FREDDY went up just west of Mobile if I remember right, While IVAN came in at Orange Beach.
Member Since: Posts: Comments:
Quoting PensacolaDoug:
I've lived in Pensacola, right by the water, all of my life. I'm 50. I went thru Eloise in '75, Frederic in '79, Elena in '85, Erin and Opal in '95, Georges in '98. The point of all this is that I considered myself a "hurricane vetern" after experiencing all of those storms. That all changed on Sept, 15, 2004 when IVAN blew thru and re-defined my definition of a hurricane. Those other storms could not compare to ferocity and level of violence and damage that IVAN caused. I'm cured. I don't ever want to see that again.
You went through Eloise? I would like to hear your experience on that. Eloise was a weird and powerful storm.
Member Since: Posts: Comments:
Never seen so much use of the word Decoupled and so misused and its only July 7th!
Member Since: Posts: Comments:
Quoting StormW:
INVEST 96L / TROPICAL SYNOPSIS ISSUED 7:30 A.M. JULY 07 2010

Mornin' Storm! Thanks for the update!
We'll be leaving for FL July 17 - see what you can do to keep the storms at bay! lol
Member Since: Posts: Comments:
hey doug actually freddy was a stronger storm than ivan at landfall. it was closer to sw al se ms on landfall. freddy was stengthening at landfall while ivan was weaker. actually as far as winds go only camille was stonger than freddy at landfall. freddy was also the costliest storm to hit the us at that time. not being picky but ask the folks on dauphin island what was worse for them freddy or ivan? they had thier island cut in two, and lost thier whole bridge. if orange beach and gulf shores were as built up in 1979 as they were in 2004 they may never rebuilt to that level lol. the only reason i state this is to me freddy is a ignored storm. in us landfalls, in the last 40 years, only hugo, andrew, camille, and charley had higher sustained winds than freddy at landfall and it was much larger than andrew and charley.fredrick the forgotten storm.
Member Since: Posts: Comments:
Quoting belizeit:
Do you think this qualifies already for a depression


I don't, but one of the models did.
Member Since: Posts: Comments:
aspectre "How is crude getting into LakePontchartrain? Storm waves upon high tide overtopping the coast? Or leaving Rigolets/etc open for boat traffic instead of blocking the passages?
120 tkeith "both... Oh, and the booms dont work either. I spent 2 years building the new Rigolets Bridge and the currents at the Rigolets are comparative to river currents. I've spent alot of time on Pontchatrain, it makes me physically ill to see this."

My experiences were the coastal areas west of NewOrleans. It tightens my gut to think about them getting slimed... and about what it must be doing to the people who made their living/lifestyle there (though I s'pose things have changed so much that the lifestyle in my memories is mostly a thing of the past).
But I was thinking in terms of totally blocking inflow: eg dredging LakePonchartrain and dumping the mud&shells&etc into the passages. Too strong a current?
Member Since: Posts: Comments:
Quoting belizeit:
Do you think this qualifies already for a depression

no, why would it.
Member Since: August 26, 2008 Posts: 0 Comments: 2182
The COC of 96L is just off shore 21.3N 90.3W
Member Since: Posts: Comments:
MahFL- are you in Jacksonville???!
Member Since: Posts: Comments:
RE: 156.

Uncalled for dude.
Member Since: Posts: Comments:
Quoting StormSurgeon:


Sorry, sat on a cactus this morning.....LOL


LOL :)
Member Since: Posts: Comments:
.
Member Since: Posts: Comments:
Quoting StormSurgeon:


Sorry, sat on a cactus this morning.....LOL

Ouch!
Member Since: Posts: Comments:
Quoting HurricaneSwirl:


Wow, way to nitpick LOL. Although I don't think you were trying to start an argument, and you're technically more correct.. but isn't a numeric designation just a type of name?


Sorry, sat on a cactus this morning.....LOL
Member Since: Posts: Comments:
I've lived in Pensacola, right by the water, all of my life. I'm 50. I went thru Eloise in '75, Frederic in '79, Elena in '85, Erin and Opal in '95, Georges in '98. The point of all this is that I considered myself a "hurricane vetern" after experiencing all of those storms. That all changed on Sept, 15, 2004 when IVAN blew thru and re-defined my definition of a hurricane. Those other storms could not compare to ferocity and level of violence and damage that IVAN caused. I'm cured. I don't ever want to see that again.
Member Since: Posts: Comments:
Quoting FLdewey:


And an invest labeled in the 70's is a DISCO INVEST!


LOL!
Member Since: Posts: Comments:
Quoting StormSurgeon:


Sorry, It's not a "name", it's a numeric designation.


Wow, way to nitpick LOL. Although I don't think you were trying to start an argument, and you're technically more correct.. but isn't a numeric designation just a type of name?
Member Since: Posts: Comments:
Quoting MahFL:
Don't get me wrong, ideally I'd like a nice cat 1....but if a cat 3 comes....we are out of here !!!!


"Ideally", you'd log off........
Member Since: Posts: Comments:
Quoting MahFL:


They will go where they go, my desires do not matter.
That's a fact...
Member Since: Posts: Comments:
Quoting Orcasystems:


AOI
Do you think this qualifies already for a depression
Member Since: Posts: Comments:
Also an INVEST labeled in the 80's in a TEST INVEST
Member Since: Posts: Comments:


AOI

AOI

AOI

AOI

TS BUSTED FORECAST ALIBI
Member Since: Posts: Comments:
Quoting MahFL:


I want to see Hurricanes.
Aimed at your house, taking off the roof, blowing out the windows, and you digging out of your attic to get on your roof, because the water is rising rapidly in your house; when you finally get on your roof at 2 A.M., sometime in August, you wait for hours for rescue, and finally 12 hours later the copter plucks you off, but oh no, you are dropped, and swept away a bit, until you see a mattress floating by, which you end up on. You finally make it to dry ground. That should be the fate of people wishing for disasters like hurricanes, because, although most in hurricanes do not end up in such horrific situations, some do, and some die. Think before you wish for something that could put people in harms way, because for the most, this is what happened to my friend.
Member Since: August 5, 2007 Posts: 0 Comments: 719
149. MahFL
Don't get me wrong, ideally I'd like a nice cat 1....but if a cat 3 comes....we are out of here !!!!
Member Since: Posts: Comments:
Quoting HurricaneSwirl:


It's the name the NHC gives them. When the NHC decides that an area of interest or of concern has enough of a chance to develop, they declare it an invest, which is just short for investigation. The first name is 90L, then 91L, then 92L, and so on. Once it gets past 99L, it goes back to 90L. In other basins the letter on the end would be different. East Pacific would be 90E, West Pacific would be 90W, North Indian in the Bay of Bengal would be 90B, North Indian in the Arabian Sea would be 90A, etc.


Sorry, It's not a "name", it's a numeric designation.
Member Since: Posts: Comments:
Quoting MahFL:


Nope I am 47 and married with two teen stepkids.
I am also an Advanced Skywarn Spotter.

My apologies....just wasn't sure where the desire to have a hurricane came from.
Member Since: Posts: Comments:
146. MahFL
Quoting MahFL:


Nope I am 47 and married with two teen stepkids.
I am also an Advanced Skywarn Spotter.


Also my father in law lost his house in Katrina.
Hurricanes happen, you can't stop them.....
Member Since: Posts: Comments:
Thanks!
Member Since: Posts: Comments:
Quoting hurricanehanna:

I'm going to go out on a limb here and guess that you are young. Yes, weather can be thrilling - I used to love the idea as a youngster of a hurricane. It meant a day off from school. But as an adult, with a home, a family and older family members to worry about...not so much.
Agreed....I moved out here from California, and Andrew hit 3 months later...I thought it was kind of neat at first...However after going through that, Allison, Lili, Rita, Gustav, and Ike, that changed my mind very quickly.
Member Since: Posts: Comments:
Quoting hurricanehanna:

I'm going to go out on a limb here and guess that you are young. Yes, weather can be thrilling - I used to love the idea as a youngster of a hurricane. It meant a day off from school. But as an adult, with a home, a family and older family members to worry about...not so much.


Yes, I've seen it through the eyes of my children and it changes everything. They are still horrified of the destruction.
Member Since: Posts: Comments:
142. MahFL
Quoting hurricanehanna:

I'm going to go out on a limb here and guess that you are young. Yes, weather can be thrilling - I used to love the idea as a youngster of a hurricane. It meant a day off from school. But as an adult, with a home, a family and older family members to worry about...not so much.


Nope I am 47 and married with two teen stepkids.
I am also an Advanced Skywarn Spotter.
Member Since: Posts: Comments:
141. MahFL
The invest numbers don't really mean much, they go from 90 to 99 and are re-used as needed.
Member Since: Posts: Comments:
Quoting MahFL:


They will go where they go, my desires do not matter.

I'm going to go out on a limb here and guess that you are young. Yes, weather can be thrilling - I used to love the idea as a youngster of a hurricane. It meant a day off from school. But as an adult, with a home, a family and older family members to worry about...not so much.
Member Since: Posts: Comments:
500 mb heights/temp analysis for CONUS superimposed on IR imagery:

Link

596 dm ridge centered over W Va. Y'all can cook yer rashers and boil yer poteen right on the pad. (ok, i don't really know what they eat down there)
Member Since: Posts: Comments:
JB this morning.

WEDNESDAY 7:45 AM

Nothing says lovin' like baking in the oven.

The numbers are too low again today in the I-95 corridor, though New england will cool down. But I expect each of my four duel cities to hit 100 again today and the latest numbers do not show that, stopping it a 99 in DC and BWI and PHL at 98, newark at 97. Though the flow is northeast, it is coming from areas that cooked yesterday and it wont be until after the true heating of the day that air off the ocean can get back in. Tomorrow and Friday will be "regular " heat wave days, just in the 90s inland, 80s coast. The question is when is the next time DC fails to hit 90, or when is the next time temps in the target areas are failing to reach normal. The "cool down" this time may be a 6 day period of hot humid weather, before what I believe will the be the hottest weather of the summer for the midwest and northern plains next week hooks up and recharges the northeast heat. Chicago will have their run at 100 after the 15th, and Minneapolis is likely to hit that too.

This is going to be DC day to cook. The north to northeast wind should be strong enough so the Potomac breeze cant get in and downwind from PHL and BWI. Its between them and Baltimore today for the winner of the duel cities.

This is going to be a huge bashing of the CFS and NOAA July forecast. Equal chances does not hack it for a top 10 hot July month in the northeast, and in a worst case, top 2 or 3. The rain shadow developing in the plains will hold them on for a time, but that may even disappear. About the only place that could be below normal is a place NOAA has above, west Texas. Its amazing watching the CFS badktrack on that the past 2 weeks too.

Summer is the time of highest skill scores with the models. This has got to be the worst US model performance, and with it, the NOAA/IRI summer idea I have ever seen. It went completely against other models from other lands, which had the kind of warmth that I had forecasted. It is amazing what I am seeing going on today with the government and one can see it in the environmental sciences as profoundly as anything else. And you are darn right I am going to point that out, because I will point out facts since its open season on anyone disagreeing, and I am going to shout the truth as loud as I can.

Now here is something I am telling my clients, and you folks in se New england look out, because the water is uncommonly warm south of you and its obvious the tropical wave is going to get entrained into this upper low backing southwest:


In the atlantic, the tropical wave south of Bermuda will get entrained into the upper low backing southwest and low pressure may develop off the Carolinas Friday over some very warm water. This could "feedback" quickly developing a warm core looking, but strong winds and heavy rains would probably be confined to areas east of the center, which is likely to stay off the mid atlantic coast and skirt New England over the weekend. The greatest threat for high winds and heavy rains is over southeast New England, and given TPC's track record, one can never tell if they would actually classify this, especially since at this time, they have not given any indication they are even considering this happening.

Moral is things could get pretty interesting Saturday night and Sunday morning, no matter what the origins are. This will have energy from non tropical sources, and the trough coming from the west over the weekend may enhance the feedback. But remember Danny last year, blowing up after they took the name off. Same kind of thing can happen for se New Englanders with this as the energy that comes from the west adds to whatever comes from the south.


In the gulf, obviously some fun and games. One of my astute subscribers pointed out the cold water off the Yucatan may be inhibiting convection with the gulf system. Good point. That being said, the track of this looks a bit north of Alex and there is danger of feedback development in the Texas coastal waters later tonight and tomorrow before landfall. That is what the HWRF is trying to do. The best news: by tomorrow night its inland. However this is exactly the kind of system where tropical storm conditions can develop and TPC is behind, or wont name it. However until I can see how this looks on the visible pics, suffice it say a 12-18 hour period of squalls to gale force and seas to 10 feet are coming into the Texas coastal waters ( its already occurring in the central gulf, but well away from what looks to be the mid level rotation center, near 22 north and 90 west. Heavy rains from this will add to the woes of those in Mexico, where Alex rain caused major flooding.


THANKS FOR READING, CIAO FOR NOW *******
Member Since: Posts: Comments:
Quoting kinsingmonster:
What does the number eg "96" "91" mean when identifiying the Invest wave?


It's the name the NHC gives them. When the NHC decides that an area of interest or of concern has enough of a chance to develop, they declare it an invest, which is just short for investigation. The first name is 90L, then 91L, then 92L, and so on. Once it gets past 99L, it goes back to 90L. In other basins the letter on the end would be different. East Pacific would be 90E, West Pacific would be 90W, North Indian in the Bay of Bengal would be 90B, North Indian in the Arabian Sea would be 90A, etc.
Member Since: Posts: Comments:

Viewing: 187 - 137

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 | 37Blog 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.

Local Weather

Overcast
30 °F
Overcast

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron