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MAY 2001 WEATHER REVIEW

FROST IN EARLY MAY!!!  RECORD HEAT LATE!!!!

A month of extremes to say the least. Perhaps in response to the dramatic Solar activity of last month, FROST was noted at the bottom of the hill I live on the 2nd.  While temps at my place only reached 43F, the air was so still for a few hours before dawn, and with origins from the north, the coldest air settled  into the lowest valleys and created this highly unusual event. By 0930, winds were back up and gusting to near 30mph..The frost was a full 3-4 weeks later than anything I can remember. An interesting side note to this event, while it was dead calm here, winds were clocked at 50+ mph in the East Bay hills with damaging winds reported elsewhere. While we are often sheltered from the strongest winds, we always get some...except this time. Reports coming in from agri-business interests are saying that last month's (April) and May's cold may have taken a heavy toll on crops over a wide range of varieties, with damage heaviest in the northern sections of the state, with damage in the Central parts also reported.  Hardest hit appears to have been the wine and fruit  producers.
We were hard pressed to see any clouds at all (excluding the fog, that is), as only .03" of precip (in the form of drizzle) fell. However, trees and virtually all forms of flora are lush this Spring, primarily due to moderate Winter rains, overall cool temps interspersed with periods of warmth, and the mild Summer and Autumn temps of last year, all coupled  with lower than normal fire seasons over the last few years. This year, things are likely to be different as fire officials have already raised the Red Flag alerting residences of an extremely high fire danger for the upcoming fire season.  
After the frost on the 2nd, things got roaring hot by the 30th, setting all kinds of records including an unbelievable 101F in San Francisco, and 92 (briefly) here. In Spring Valley, the "official" RAWS site about nestled in the coastal hills 3 miles from here as the crow flies, temps hit 96. By comparison, San Francisco's alltime high is 104 and 96 here in Pacifica, so here in May we neared hottest-ever conditions. An interesting note is the record highs mentioned above occurred just last year on June 14, so the current "La Nada" weather pattern seems to be anything but "nothing". Can't help but think that the intense Solar activity in April as mentioned a while back set the stage for the unusual extremes noted this month.

And now, the data.

                   MONTHLY CLIMATOLOGICAL SUMMARY for MAY. 2001


NAME: HOME CITY: Pacifica  STATE: Ca  ELEV: 540'  LAT: 37.36'N  LONG: 122.27'W 


                   TEMPERATURE (°F), RAIN  (in), WIND SPEED (mph)


                                      HEAT  COOL        AVG
    MEAN                              DEG   DEG         WIND                 DOM
DAY TEMP  HIGH   TIME   LOW    TIME   DAYS  DAYS  RAIN  SPEED HIGH   TIME    DIR
------------------------------------------------------------------------------------
 1  54.4  63.7   8:45a  46.7  12:00m   9.8   0.0  0.00   3.1  17.0   2:00a   SSW
 2  60.2  71.4   5:30p  43.8   5:45a   7.4   0.0  0.01   5.4  28.0   9:15a     N
 3  65.1  75.8   2:00p  51.4  12:00m   1.4   0.0  0.00   4.7  24.0   7:45a     N
 4  60.2  74.1   2:15p  48.9   4:30a   3.5   0.0  0.00   1.7  11.0  11:00a    NE
 5  57.3  67.1   2:45p  47.7   5:15a   7.6   0.0  0.00   2.2  10.0  12:00p   SSW
 6  58.7  71.8   1:30p  46.1   4:45a   6.0   0.0  0.00   1.8   9.0  11:30a   SSW
 7  65.8  84.5  11:30a  50.1   1:30a   0.0   2.3  0.00   1.9  15.0  10:15a     S
 8  62.0  77.5  12:15p  50.8   5:30a   0.8   0.0  0.00   1.7  10.0   2:00p   SSW
 9  56.1  67.8   8:45a  48.2   6:00a   7.0   0.0  0.00   2.6  16.0   6:30p   SSW
10  60.0  72.8   3:15p  46.6   4:15a   5.3   0.0  0.00   1.6   9.0  11:45a    NW
11  60.1  74.2  12:45p  50.8   5:15a   2.5   0.0  0.00   2.9  19.0  11:00a     W
12  55.6  62.5   3:00p  52.5   4:15a   7.5   0.0  0.00   5.2  22.0   9:00a     S
13  54.8  60.1   1:00p  51.7   4:15a   9.1   0.0  0.00   4.9  17.0  12:45p     S
14  57.2  64.0   2:00p  51.8   3:45a   7.1   0.0  0.00   3.5  16.0  11:15a   SSW
15  59.7  68.8   2:00p  52.4   5:00a   4.4   0.0  0.00   2.1  11.0   2:30p   SSW
16  57.0  64.4  12:30p  52.8  12:00m   6.4   0.0  0.02   3.0  18.0   4:00p   SSW
17  57.2  66.4  11:00a  51.6  12:00m   6.0   0.0  0.00   3.1  13.0   3:00p   SSW
18  57.2  65.4  10:00a  50.1   3:30a   7.3   0.0  0.00   2.3  11.0   1:30a   SSW
19  62.5  75.3   2:30p  49.1   5:00a   2.8   0.0  0.00   1.8  10.0  12:30p   SSW
20  60.0  70.9   2:00p  49.8   5:30a   4.7   0.0  0.00   1.8   9.0  10:30a   SSW
21  62.8  77.3   1:30p  50.6   5:30a   1.0   0.0  0.00   1.8  11.0   1:00p     S
22  59.9  72.6  12:30p  50.8   5:30a   3.3   0.0  0.00   2.0  10.0   1:00p     S
23  56.7  67.5  12:00p  49.8  12:00m   6.3   0.0  0.00   2.0  11.0   5:30p   SSW
24  56.3  64.5  12:00p  47.8   5:30a   8.8   0.0  0.00   1.6  10.0  12:00p   SSW
25  55.0  62.5   1:00p  50.4  12:30a   8.5   0.0  0.00   2.2  10.0   4:30p   SSW
26  53.0  56.7   2:00p  50.6   5:30a  11.3   0.0  0.00   3.5  13.0   2:30p   SSW
27  54.0  60.8  12:30p  50.9   6:30a   9.2   0.0  0.00   4.6  19.0   2:30p   SSW
28  54.9  60.0   2:30p  51.8  12:00m   9.1   0.0  0.00   5.4  22.0   6:30a   SSW
29  57.3  66.9   3:00p  47.8   6:00a   7.7   0.0  0.00   2.3  10.0   2:00p   SSW
30  72.5  91.3   1:30p  51.6  12:30a   0.0   6.4  0.00   2.2  22.0  12:30p     N
31  72.8  86.5   1:00p  59.3  12:00m   0.0   7.9  0.00   1.4  12.0   3:00p   WSW
-------------------------------------------------------------------------------------
    59.2  91.3    30    43.8     2   171.9  16.7  0.03   2.8  28.0     2     SSW


Max >= 90.0:  1
Max <= 32.0:  0
Min <= 32.0:  0
Min <=  0.0:  0
Max Rain: 0.02 ON  5/16/01
Days of Rain: 1 (>.01 in) 0 (>.1 in) 0 (>1 in)
Heat Base:  65.0  Cool Base:  65.0  Method: (High + Low) / 2