Early frost possible for Minneapolis Friday night...
Posted: Thu Sep 13, 2007 7:29 am
The forecast for Minneapolis for Friday night is calling for lows between 30 and 35. Considering the early cooldown up in the Upper Midwest I have a good feeling they will be in for a good winter. The last 5 early frosts in the Minneapolis area (before 10/1, where the low at MSP was 35 or lower during the month of September) have corresponded to very snowy Upper Midwest winters. 1991, 1995, 1996, 2000, and 2003 were the last five times where Minneapolis had a September frost. In each of those years the following winter was very good for MSP.
91-92: 84.1"
95-96: 55.5"
96-97: 72.1"
00-01: 75.8"
03-04: 66.4"
Going back into the 80's this happened four additional times:
1981, 1983, 1985, 1989
Snowfall those winters:
81-82: 95.0
83-84: 98.4
85-86: 69.5
89-90: 35.5
89-90 was the exception to this trend as it was the only year of the 9 to feature below normal snowfall for MSP (which is around 46" for 122 years of data). 8 of 9 years with above normal snow is a very valid trend for a colder/snowier winter in that location. I do know that many of those winters in Minneapolis were quite cold as well, with temperatures significantly below normal in 83-84, 95-96, and 96-97.
Equating this to Philadelphia...here is what I get for snow/temperatures, with the normals being ~20" of snow and 34.8 for temperature.
TEMP
81-82: 31.2
83-84: 32.7
85-86: 32.7
89-90: 35.7
91-92: 37.6
95-96: 31.9
96-97: 37.6
00-01: 33.7
03-04: 32.8
SNOW
81-82: 25.4
83-84: 21.6
85-86: 16.4
89-90: 17.0
91-92: 4.7
95-96: 65.6
96-97: 12.9
00-01: 26.1
03-04: 18.0
Temp distribution is 3 above, 6 below normal
Snow distribution is 4 above, 5 below normal
Taking this a step further, of those 9 winters, only 89-90 and 91-92 were not neutral or nina at the end of winter. 89-90 was developing a nino by the end of winter while 91-92 was a rather strong nino. With the seven other winters taken to a national level the trend was for colder than normal weather for much of the eastern half of the country.
91-92: 84.1"
95-96: 55.5"
96-97: 72.1"
00-01: 75.8"
03-04: 66.4"
Going back into the 80's this happened four additional times:
1981, 1983, 1985, 1989
Snowfall those winters:
81-82: 95.0
83-84: 98.4
85-86: 69.5
89-90: 35.5
89-90 was the exception to this trend as it was the only year of the 9 to feature below normal snowfall for MSP (which is around 46" for 122 years of data). 8 of 9 years with above normal snow is a very valid trend for a colder/snowier winter in that location. I do know that many of those winters in Minneapolis were quite cold as well, with temperatures significantly below normal in 83-84, 95-96, and 96-97.
Equating this to Philadelphia...here is what I get for snow/temperatures, with the normals being ~20" of snow and 34.8 for temperature.
TEMP
81-82: 31.2
83-84: 32.7
85-86: 32.7
89-90: 35.7
91-92: 37.6
95-96: 31.9
96-97: 37.6
00-01: 33.7
03-04: 32.8
SNOW
81-82: 25.4
83-84: 21.6
85-86: 16.4
89-90: 17.0
91-92: 4.7
95-96: 65.6
96-97: 12.9
00-01: 26.1
03-04: 18.0
Temp distribution is 3 above, 6 below normal
Snow distribution is 4 above, 5 below normal
Taking this a step further, of those 9 winters, only 89-90 and 91-92 were not neutral or nina at the end of winter. 89-90 was developing a nino by the end of winter while 91-92 was a rather strong nino. With the seven other winters taken to a national level the trend was for colder than normal weather for much of the eastern half of the country.
