Thursday July 21, 2011
Excessive Heat

Exceptional and rare prolonged levels of heat developed over New York and western New England on this day as a super heated air mass, which had been sitting over the midwest and upper Mississippi valley for several days prior, moved into the Northeast (850 mb temperatures climbed from +20° C at 8am to +23° C, measured at 8pm). The temperature at Albany climbed to 91° and heat index to 100° at noon. The temperature and heat index then remained above 90° and 100° respectively for an incredible ten consecutive hours through 9pm.

This super heated air mass, in combination with a moderately strong southwesterly boundary layer flow of 15-35 mph through the bottom couple of thousand feet in the atmosphere created a highly favorable downslope wind scenario into especially the Capital Region and Hudson valley which caused the air to heat further as it descended along the eastern slopes of the higher terrain of the Catskills, compressing and thus warming it further. The result was the highest temperatures in the Capital Region in sixteen years with Albany's high reaching 99°, a temperature not seen since July 14, 1995, the day prior to the super derecho which ravaged the entire region with widespread damaging wind. The downslope compressional warming process is also a drying process which typically means the dewpoints go down by a good margin. In this case, however, the dewpoints only dropped by a couple of degrees, remaining above 70° all day creating a prolonged period of absolutely oppressive heat conditions with a peak heat index at Albany of 110° at 6pm. Despite the high heat and humidity, no record high was achieved with the record for this date remaining 101° set in 1930. The morning low temperature of 76° @ Albany, however, did set a record "High" minimum, breaking the prior record of 74° set in 1926

A strongly capped atmosphere (very warm air aloft) prevented any significant thunderstorms from forming. Only a few isolated brief showers/thunder showers occurred during the late afternoon and early evening, otherwise the day was generally dry. So despite conditions in the atmosphere being similar to those of July 14, 1995, no severe weather occurred due to a stronger cap and lack of any upstream trigger mechanism to produce thunderstorms.

Albany's Heat Trace

Time Temperature Dewpoint Heat Index Wind
Noon
91°
73°
100°
South 13 mph
1pm
94°
74°
105°
South 14 mph
2pm
96°
70°
104°
SW 12 mph
3pm
97°
71°
106°
SSW 10 mph
4pm
98°
72°
109°
SW 12 mph
5pm
99°
71°
109°
SW 14 mph
6pm
98°
73°
110°
WSW 7 mph
7pm
96°
73°
107°
SW 8 mph
8pm
93°
73°
103°
SW 7 mph
9pm
91°
73°
100°
SW 7 mph
10pm
88°
74°
97°
South 5 mph
11pm
86°
74°
94°
South 5 mph

Regional Heat Numbers: WeatherNet 6 and Local ASOS Reports

Town County High Temperature
North Adams, MA Berkshire 95° - Peak Heat Index: 101°
Pittsfield, MA Berkshire 93° - Peak Heat Index: 97°
Alford, MA Berkshire 95°
     
Colonie Albany 99° - Peak Heat Index: 107°
Pine Bush Albany 100°
Newtonville Albany 98°
Feura Bush Albany 99°
Glenmont Albany 97°
Cohoes Albany 98°
Medusa Albany 95°
     
Landgrove, VT Bennington 88°
Bennington, VT Bennington 94° - Peak Heat Index: 101°
     
North Chatham Columbia 97°
Ancramdale Columbia 93°
Livingston Columbia 98°
Taghkanic Columbia 96°
Hudson Columbia 101°
     
Red Hook Dutchess 100°
Poughkeepsie Dutchess 98° - Peak Heat Index: 105°
     
Broadalbin Fulton 96°
Gloversville Fulton 98°
     
Catskill Greene 100°
Round Top Greene 98°
Halcott Greene 91°
     
Hoffmeister Hamilton 89°
Lake Pleasant Hamilton 90°
     
Amsterdam Montgomery 98°
Palatine Bridge Montgomery 96°
Fonda Montgomery 96°
     
Oneonta Otsego 96°
East Worcester Otsego 92°
     
Schaghticoke Rensselaer 94°
     
Danby, VT Rutland 87°
     
Moreau Saratoga 98°
Milton Saratoga 99° - Peak Heat Index: 112°
Charlton Saratoga 95°
Saratoga Springs Saratoga 98°
     
Duanesburg Schenectady 95°
Scotia Schenectady 97°
     
Middleburgh Schoharie 95°
Gilboa Schoharie 90°
Summit Schoharie 93°
Fulton Schoharie 98°
Jefferson Schoharie 95°
     
Ulster Park Ulster 98°
Kerhonkson Ulster 97°
Whiteport Ulster 101°
West Shokan Ulster 96°
Phoenicia Ulster 92°
Saugerties Ulster 97°
     
Cossayuna Washington 93°
Eagle Bridge Washington 97°
     
Glens Falls Warren 96° - Peak Heat Index: 105°

Friday July 22, 2011
Excessive Heat

Significant to excessive heat continued across the region on this day. However, different from Thursday July 21, a considerable break from the oppressive humidity occurred with the passage of a dewpoint front during the morning. Dewpoints fell from the sky high mid 70s in the Capital Region early in the morning into at one point the lower 50s (due to mixing of dry air aloft down to the ground) during the afternoon. The net result was peak heat index values not going above 95° vs 110° heat index values on the 21st. A pleasant breeze, gusting at times to 20-25 mph aided in the more comfortable feel to the air, vs. the air on the 21st where the wind produced blast furnace like conditions at times. Temperatures, however, remained quite hot, with readings ranging from the lower to mid 90s on average except in the mid Hudson valley, including eastern Greene, Columbia, Ulster, Dutchess, and Litchfield counties where high temperatures ranged from 97° to 102° with heat index values up to 110°. The dewpoint front only made it into the mid Hudson valley during the mid to late afternoon which allowed oppressive heat conditions to prevail much of the day with lower sixty degree dewpoints not arriving until the early evening.

Regional Heat Numbers: WeatherNet 6 and Local ASOS Reports

Town County High Temperature
Pittsfield, MA Berkshire 92°
Alford, MA Berkshire 92°
     
Newtonville Albany 95°
Glenmont Albany 96°
     
Landgrove, VT Bennington 87°
     
North Chatham Columbia 98°
Ancramdale Columbia 97°
Livingston Columbia 99°
Taghkanic Columbia 98°
     
Red Hook Dutchess 99°
Poughkeepsie Dutchess 102°
     
Broadalbin Fulton 87°
     
Hoffmeister Hamilton 86°
     
Amsterdam Montgomery 88°
Hessville Montgomery 89°
Fonda Montgomery 91°
     
East Worcester Otsego 92°
Oneonta Otsego 96°
     
Danby, VT Rutland 88°
     
Milton Saratoga 94°
Charlton Saratoga 91°
Saratoga Springs Saratoga 97°
     
Middleburgh Schoharie 95°
Gilboa Schoharie 90°
Summit Schoharie 94°
Fulton Schoharie 96°
Jefferson Schoharie 90°
     
Kerhonkson Ulster 99°
Whiteport Ulster 101°
West Shokan Ulster 102°
Phoenicia Ulster 94°
Saugerties Ulster 97°
Esopus Ulster 99°
Kingston Ulster 100°
     
Cossayuna Washington 93°
Eagle Bridge Washington 95°

 

\