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NOVEMBER 2001 WEATHER SUMMARY
(Includes commentary on the 21st-12/2 GOA storm sequence ) See special report on  Leonids 2001 in Archives section
In a word, Windy&Wet (technical term). Our 6.3", while only the 4th wettest November in my records (to 1984), signaled what may be a generic shift in our west coast storm track. For the first time (or at least very rarely) since the drought of '76-'78, deep, windy and wet storms dropped like a conga-line along the coast from British Columbia to Los Angeles. By Dec. 2, seasonal rainfall totals had climbed >200% of normal in many locations (228% PON for Pacifica). Most rain fell in two distinct rainy periods with 11 days of rain overall. The 3 days of  rain > 1" with two of those approaching 2" days was impressive, demonstrating a rejuvenation of the moisture supply. After a warm and tranquil opening week of the month, twin lows hit the coast as "uppercuts" from the SW. High rainrates from both storms, especially storm #2, occurred when cold air invaded the lows right off the coast. Long moisture plumes from the sub-tropics resembling Pineapple Connections fueled each low, with the plumes extending down to the vicinity of 20N.  Beginning on the 21st, the second, a more significant (long-term) pattern developed during the last 10 days or so of the month, extending into early December (12/1-2) as a progression of increasingly potent GOA lows swept down the NE side of a well entrenched EPac high anchored between Hawaii and Baja. High winds accompanied all the lows,  indicating good surface dynamics (as compared to the now dreaded "Upper Level" and "Cutoff" low pressure patterns of the past few years) with winds topping out at 60mph in Pacifica on the 24th.  This event came right on the heels of a drier but deeper inside-slider type low passage on the 23rd when winds pummeled the entire state, reaching 114mph in Kern Country and 80-90mph in the Mojave desert. Hi winds also occurred with the three big rain makers from the 28th-12/2, topping out in Pacifica at 59, 54 and 51 mph respectively. Wind gusts over 100mph were noted over the higher Sierra ridges on the 28th and again on Dec. 2.  Minor wind damage occurred over a large area of the State, and power outages affecting over 500,000 Customers resulted from the blow on the 24th. During the 21st-Dec. 2 period,  almost 9"  of rain fell....over 7" from the 28th thru Dec. 2., with snow to very low elevations in the north part of the state. On the 28th, over 24" of snow buried NorCal above 3,500', shutting down I-5 for 12 hrs over a 150  mile stretch. . Another interesting aspect of rains this month was the dramatic orographic enhancement of rain totals. Pacifica seems to have been right in "The Zone", as our 228% PON (12.39")  is significantly higher than surrounding areas. SFO (the airport on the other side of The Peninsula) for instance, is also wetter than San Francisco, and reflects the older pattern of SFO being wetter than The City. Note that for most of the non-El Nino years since '76-'78, The City has averaged more rain than SFO. During many of this year's November storms, rainfall often ranged from tenths to 2-4" in the immediate Bay Area depending on the amount of  (or lack of) orographic lifting. Both wind direction and intense surface flows have contributed to this effect. It was interesting to note that up until the end of the month, rainfall inland and snowfall in the Sierra were only average at best. However, the Dec 1 & 2 storms ended the "average" aspect of our Winter so far, depositing widespread 3-5' blankets down 5,500', with smaller amounts down to 3,500'. Other quick notes: High surf has caused enhanced erosion in many locales, some minor damage to cliffs and the Pacifica Pier,  minor flooding in lower Linda Mar accompanied the 5.3" dump during 24hrs of 12/1-12/2, convective activity noted on the 24th, 28th and Dec 2nd, pea hail fell on the 28th and Dec. 2.

                   MONTHLY CLIMATOLOGICAL SUMMARY for NOV. 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  55.9  66.5   1:00p  50.4   8:00a   6.5   0.0  0.01   1.1  11.0   1:00p     S
 2  55.2  66.0   1:30p  47.9   7:00a   8.0   0.0  0.01   0.9  10.0   1:30p   SSW
 3  54.1  64.9   1:30p  48.4   7:30a   8.3   0.0  0.00   1.1   9.0  12:00p   SSW
 4  53.2  64.1   2:00p  47.4   6:30a   9.3   0.0  0.00   1.0  10.0   1:00p   SSW
 5  55.7  64.8   1:30p  50.7   8:30a   7.3   0.0  0.00   1.7   8.0  10:30a   SSW
 6  52.9  58.6   2:00p  47.4  12:00m  12.0   0.0  0.00   3.5  18.0   1:00p     S
 7  55.6  66.6   3:00p  46.3   5:30a   8.6   0.0  0.01   2.6  16.0  12:00p     N
 8  63.8  72.8   3:00p  58.0  11:00p   0.0   0.4  0.00   3.0  14.0   4:30a     S
 9  60.4  71.8   1:30p  51.8  12:00m   3.2   0.0  0.00   1.4   9.0  11:00a     S
10  57.3  64.6  12:30p  49.3   4:00a   8.1   0.0  1.11   3.5  33.0   3:00p     S
11  60.4  62.5   1:30p  58.3   1:00a   4.6   0.0  0.19   8.1  36.0   1:30p     S
12  57.2  60.7  12:30a  53.8   8:00p   7.8   0.0  1.84   6.4  36.0  12:30a     S
13  56.2  60.3  11:30a  52.5   5:00a   8.6   0.0  0.01   2.5  15.0  12:00p   SSW
14  58.9  64.3  12:00p  55.0  12:00m   5.3   0.0  0.00   1.1   8.0  10:30a   SSW
15  56.0  62.1  11:30a  53.2  12:00m   7.3   0.0  0.01   1.0  11.0   6:00a    SW
16  57.5  64.1   1:00p  52.5   7:00a   6.7   0.0  0.02   1.8  15.0  12:30p     S
17  55.0  62.3   2:00p  48.3   7:00a   9.7   0.0  0.01   1.6  15.0   9:30p     S
18  57.8  65.1   2:00p  51.7   5:00a   6.6   0.0  0.00   3.0  20.0   9:30a   WNW
19  58.6  62.2   4:00p  53.3   6:30a   7.3   0.0  0.02   3.9  27.0   3:00p     S
20  61.4  66.9   1:00p  59.0   6:30a   2.0   0.0  0.00   3.0  17.0  11:00p     S
21  59.4  61.6  11:30a  58.0   6:00p   5.2   0.0  0.20   7.5  34.0   4:00p     S
22  57.7  60.9   1:00p  53.1  11:30p   8.0   0.0  0.00   3.9  24.0  12:30a     S
23  54.8  59.1  12:30p  51.0   6:30a  10.0   0.0  0.00   1.7  13.0  12:30p     S
24  52.6  59.4   7:30a  46.7  12:00m  11.9   0.0  0.85   8.7  60.0   7:30a     S
25  49.3  54.7   2:00p  44.8   3:00a  15.3   0.0  0.02   1.0   9.0  12:30a     S
26  49.6  55.6   1:30p  45.1  12:00m  14.7   0.0  0.00   1.4  12.0  12:00p   NNW
27  47.9  54.4   3:00p  43.3   6:00a  16.2   0.0  0.00   2.3  17.0   2:00p    NE
28  51.2  54.5  11:00a  47.3  12:30a  14.1   0.0  1.86   9.9  59.0   9:00p     S
29  52.1  55.8   2:30p  49.3  12:00m  12.5   0.0  0.09   4.6  21.0   7:30p     S
30  50.1  56.9   2:30p  44.3   6:00a  14.4   0.0  0.04   1.8  15.0  10:30p   SSW
-------------------------------------------------------------------------------------
    55.6  72.8     8    43.3    27   259.3   0.4  6.30   3.2  60.0    24       S


Max >= 90.0:  0
Max <= 32.0:  0
Min <= 32.0:  0
Min <=  0.0:  0
Max Rain: 1.86 ON 11/28/01
Days of Rain: 11 (>.01 in) 6 (>.1 in) 3 (>1 in)
Heat Base:  65.0  Cool Base:  65.0  Method: (High + Low) / 2