My working hypothesis about the Wallow Fire is that the rather rapid fire spread to the NE from the source region and large acreage burned was largely driven by unusually persistent 15-50 mph SW winds which were a result of the same anomalous synoptic weather pattern which has resulted in an unusually cool spring throughout the West. Temperatures in May were below normal in Arizona, so we can’t blame the heat and Arizona is almost always dry in May and June so that is not unusual. If you look at Winslow AZ temperatures (see below) you will see the temperature averaged about -2 deg F below normal during the time the fire actively spread to the NE from 29 May to about 10 June. But what is striking is the wind as shown in the last 4 columns. By the way, a south wind direction is 180 and a west wind direction is 270. The wind at Winslow AZ reached 63 mph on 29 May 2011, the day the fire started.
STATION: WINSLOW AZ AIRPORT
YEAR: 2011
ELEVATION: 4938 ft
LATITUDE: 35 1 N
LONGITUDE: 110 44 W
===================================================================
12Z AVG MX 2MIN PK 3SEC
DY MON MIN MAX AVG DEP HDD CDD WTR SNW DPTH SPD SPD DIR SPD DIR
===================================================================
21 May 37 78 58 -6 7 0 0 M M 4 16 260 20 260
22 May 45 83 64 0 1 0 0 M M 9 24 190 30 200
23 May 48 80 64 0 1 0 0 M M 16 31 230 40 220
24 May 42 77 60 -6 5 0 0 M M 15 28 250 37 240
25 May 45 83 64 -1 1 0 0 M M 6 14 220 22 320
26 May 55 87 71 6 0 6 0 M M 17 36 220 43 220
27 May 48 93 70 4 0 6 0 M M 13 30 230 39 210
28 May 63 90 76 10 0 12 0 M M M 40 230 54 220
29 May 55 80 68 0 0 3 0 M M 28 48 190 63 200
30 May 40 74 57 -10 8 0 0 M M 4 18 230 35 320
31 May 38 89 64 -4 1 0 0 M M 9 22 210 29 210
1 Jun 56 93 74 6 0 10 0 M M 12 30 200 38 210
2 Jun 44 86 65 -3 0 0 0 M M 12 31 200 39 230
3 Jun 41 86 64 -4 1 0 0 M M 11 30 200 38 220
4 Jun 45 91 68 -1 0 3 0 M M 12 30 210 46 220
5 Jun 49 95 72 3 0 7 0 M M 11 30 210 38 210
6 Jun 50 89 70 0 0 5 0 M M 17 39 190 49 200
7 Jun 44 89 66 -4 0 2 0 M M 11 24 210 32 210
8 Jun 45 88 66 -4 0 2 0 M M 13 33 220 48 230
9 Jun 45 87 66 -4 0 1 0 M M 7 16 250 21 250
10 Jun 50 91 70 0 0 6 0 M M 8 26 230 35 190
11 Jun 53 90 72 0 0 7 0 M M 10 25 210 33 210
12 Jun 50 91 70 0 0 6 0 M M 12 28 220 38 200
13 Jun 53 91 72 0 0 7 0 M M 11 26 250 32 240
14 Jun 53 92 72 0 0 8 0 0 0 5 10 230 14 330
15 Jun 55 99 77 5 0 12 0 0 0 10 25 230 33 230
16 Jun 59 95 77 5 0 12 0 M M 16 32 230 40 220
17 Jun 57 92 74 2 0 10 0 M M 15 31 240 46 230
18 Jun 59 93 76 3 0 11 0 M M 12 30 220 49 210
19 Jun 59 89 74 1 0 9 Tr M M 19 37 260 46 240
20 Jun 46 85 66 -8 0 1 0 0 0 6 15 340 21 330
===================================================================
Temperature - Mean Min: 49.3 Mean Max: 87.9 Range: 37 to 99
Temperature - Mean: 68.6 Dptr from Normal: -0.2 F
Total Precip: 0.00 Total Snowfall:
Mean Wind Speed: 11.6
Total HDD: 25 Total CDD: 146
Units: Temperature-deg F, Precipitation-inches, Wind-mph