Endless Summer IV: DC's 62nd Day of 90°+ Temperatures

8 PM Update: And 96° it is, at 3:46 PM EDT. Temperatures were 90° or above for 8 consecutive hours beginning at noon. The low of 74° is no slouch either, just 2° below the record highest minimum for the date, if it holds through midnight. That certainly looks feasible, although temperatures will be dropping quickly. Overall, at this rate, the day is adding 12° of surplus over the long term average.

5 PM Update: The temperature was 95° for 3 consecutive hours; that's probably good enough for a high of 96°.

2 PM Update: Preliminary high: 95°. (WaPo's non-carbonated edition forecast: "Upper 80s to near 90". Yeah, that's pretty near. NOT.)

Original post:
That crashing noise around noon today in the Washington metro area was the sound of temperature forecasts busting as the mercury once again reached 90°. It rose 3 more degrees in the following hour to 93°. This is now the 62nd day of 90°+ temperatures in 2010. Although that is still 5 days ahead of the torrid pace toward 67 days in the record-setting year of 1980, temperatures will drop to more seasonable levels for at least the rest of the week, and 2010 may, for the first time all year, drop behind the record pace.

Images (click to enlarge): Washington/Baltimore regional temperatures shortly after 1 pm EDT, Sept. 8, 2010, from Intellicast; Cumulative annual number of days 90° or higher in Washington, CapitalClimate chart from National Weather Service data

Endless Summer III: 'Nother Ninety Notched 61st Day of 90°+ Temperatures

5:30 PM Update: The preliminary high/low temperatures for Sept. 7 are 94/69. If the low holds through midnight, the first week of September will average nearly 6° above the long-term mean.

Original post:
At 3 pm today, the temperature at Washington National jumped 4° in an hour, reaching 93°. Following a record hot spring and summer, this is the 61st day of 90°+ temperatures at Washington in 2010. The record for one year is 67 in 1980. The total didn't reach 61 in 1980 until 5 days later, however.

Temperatures at other major regional reporting locations were also 90° or above; 91° at Washington Dulles and 90° at Baltimore/BWI.

Record Hot Spring-Summer in Northeast, Mid Atlantic

Images (click to enlarge): U.S. Northeast and Mid Atlantic temperature departures from average for spring (March-May) and summer 2010 (June-August) from NOAA Applied Climate Information System (ACIS)

Not only have a number of summer temperature records been set this year, but a majority of major climate reporting stations in the Northeast and Mid Atlantic (26 locations) have set or tied records for the hottest spring-summer (March-August). Here is the NOAA summary of 2010 temperatures vs. the previous records:

                                2010    Previous
                              Average Year  Average Difference
Atlantic City NJ                66.8  1991  64.5      2.3
Washington/Dulles VA            68.2  1991  66.4      1.8
New York/JFK NY                 66.3  1991  64.6      1.7
Newark NJ                       68.1  1993  66.5      1.6
Worcester MA                    60.7  1949  59.2      1.5
Providence RI                   63.9  1945  62.5      1.4
New York/LaGuardia NY           68.3  1991  66.9      1.4
Hartford/Bradley CT             64.0  1991  62.8      1.2
Washington National DC          70.9  1991  69.7      1.2
Caribou ME                      54.7  1979  53.5      1.2
Central Park NY                 67.5  1991  66.3      1.2
Philadelphia PA                 68.9  1991  67.7      1.2
Islip NY                        64.2  1991  63.1      1.1
Bridgeport CT                   64.3  1991  63.2      1.1
Wilmington DE                   67.2  1973  66.2      1.0
Boston MA                       63.4  1991  62.4      1.0
Binghamton NY                   59.7  1991  58.8      0.9
Baltimore/BWI MD                68.4  1921  67.6      0.8
Concord NH                      59.5  1921  58.7      0.8
Burlington VT                   59.4  1894  58.6      0.8
Middletown/Harrisburg PA        66.5  1991  65.9      0.6
Williamsport PA                 64.4  1921  64.0      0.4
Portland ME                     58.8  1878  58.4      0.4
Allentown PA                    64.1  1991  63.7      0.4
Syracuse NY                     61.1  1921  60.9      0.2
Scranton PA                     62.4  1921  62.4      0.0 

Five more stations had their second hottest spring-summer:

                               2010     Previous
                              Average Year  Average Difference
Albany NY                       61.6  1921  61.8     (0.2)
Elkins WV                       61.5  1921  61.7     (0.2)
Beckley WV                      62.9  1991  63.2     (0.3)
Buffalo NY                      60.3  1991  60.7     (0.4)
Rochester NY                    60.7  1921  61.6     (0.9) 

Two other stations (Charleston WV and Erie PA) had their 3rd hottest spring-summer, Pittsburgh PA had its 6th hottest, and Huntington WV had its 7th hottest.

Summer of Simmer Summary: More Heat Records Broken

As previously reported, it was the hottest summer on record by a wide margin in Washington. Record-breaking heat also extended from the Mid Atlantic area into the Southeast. Here are some other summer 2010 heat records (more records to be added as available):

Central Park NY: Hottest summer, average 77.8° vs. 77.3° in 1966. [Records began 1869]

Baltimore MD: Hottest summer, average 79.3° vs. 79.1° in 1943.

Roanoke VA: Hottest summer, average 78.2° vs. 77.4° in 1987.

Danville VA: Hottest summer, average 80.0° vs. 78.7° in 1952.

Blacksburg VA: Hottest summer, average 72.9° vs. 72.3° in 1987.

Bluefield WV: Hottest summer, average 74.5° vs. 74.2° in 2007.

Raleigh NC: Hottest summer, average 81.7° vs. 79.8° in 2007. Most June-August 90°+ days, 67 vs. 58 in 2007 and 1992.

Greensboro NC: Hottest summer, average 80.1° vs. 78.5° in 2007 and 1993. Most June-August 90°+ days, 52 vs. 50 in 1993.

Asheville NC: Hottest summer, average 75.4° vs. 75.1° in 1952.

Charlotte NC: Second hottest summer, average 81.1° vs. 81.5° in 1993.

Greenville-Spartanburg SC: Hottest summer, average 81.0° vs. 80.2° in 1952.

Savannah GA: Second longest string of 90°+ temperatures, 40 ending Aug. 14, vs. 44 ending Aug. 8, 1993.

Chattanooga TN: Second hottest summer, average 84.0° vs. 85.7° in 2007.

Image (click to enlarge): U.S. surface temperature departure from average (°C), June 1 to August 31, 2010, from NOAA/ESRL Physical Sciences Division, Boulder Colorado

Endless Summer II: Washington Adds to Record Pace of 90-Degree Streak

5:30 PM Update: The preliminary daily climate report shows the high/low as 91/77. All 3 days so far this month have been at least 10° above the long-term average. The low, if it holds through midnight, will be only 2° lower than the all-time September highest daily minimum set on this date in 1993.

Original post:Despite a high overcast from the far outer fringes of Hurricane Earl, the Washington temperature reached 90° at 4 pm today. This was the 60th day of 90° or higher temperatures at Washington in 2010, and it was achieved 6 days before the same number was reached in the record year of 1980. This puts 2010 in sole possession of second place for total 90° days in a year, behind the 67 of 1980. Today was the 6th consecutive day of 90° temperatures.

Following a cooler Labor Day weekend, 2 more 90°+ days are forecast by the middle of next week. The number of 90°+ days didn't reach 62 in 1980 until September 13. The remaining 5 days that year were September 14, 17, and 21-23.

Images (click to enlarge): Cumulative annual number of days 90° or higher, CapitalClimate chart from National Weather Service data; Visible satellite image of Hurricane Earl moving away from the Mid Atlantic coast, from intellicast.com

Schools Declare Heat Day in Maine

Sept. 7, PM Update: Schools were also closed because of excessive heat in New Hampshire, as reported by WMUR TV, Channel 9:
Heat Closes Schools, Triggers Air Quality Warning

Sept. 3, PM Update: Additional reports of heat-related school closings appear in the Kennebec Journal: Heat closes schools early

Original post:The Lewiston, ME Sun-Journal reports today that some schools in Maine closed or sent students home early on Thursday, the fourth day of a record-breaking heat wave. Schools in Rockland, Augusta, Chelsea and Gardiner were affected. Superintendents reported that they had never before experienced school closings because of heat.

Temperatures in the low and mid 90s extended well into northern Maine, where Bangor set a new record high of 94°, breaking the old record of 93° set in 1953. It was the second day in a row of record temperatures in Bangor, where records extend back to 1925. The Bangor Daily News also reported on school closings resulting from temperatures in some classrooms reaching 100°.

Image (click to enlarge): U.S. high temperatures for Sept. 2, 2010 from Unisys

Washington Held Heat Hostage: Day 59 Second Highest Total of 90-Degree Days

5:30 PM Update: The preliminary high/low report is in: 95/74. It's the 23rd 24th day this year of temperatures at 95° or higher.

Original post:At 2 pm today, the temperature at Washington bumped up by 4° in an hour to reach 93°. This is now the 59th day of 90° or higher temperatures in 2010, tying the second place record set in 1966 and 1991. The record total was set in 1980 with 67, but this year is ahead of that pace; the 59th day of 90°+ temperatures didn't occur in 1980 until September 6.