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WEATHER REVIEW JANUARY 2001
A wild a cold January brought near-normal 5 .13" of rain back to Cent. California in two distinct bursts, a nice recovery from the disastrous dryness of Nov/Dec. Very cold air set in over the entire North America with GOA lows, mostly cutoffs, cruising N-S down the coast, unable to penetrate the continental block. Decent rain returned to the region beginning 1/07 and fell for 5 straight days. After nearly 2/1/2 months of relative dryness, this rainy period (continuing the trend  from Autumn of last year of extended on/off rain periods ) culminated in a wild event on the 10th/11th when a warm frnt/cold frnt double whammy left 2.3" in it's wake. Over 5" was common in the coastal mtns south of San Jose down to the Mexican border leaving the NW with much lighter precip. Winds were clocked to 60mph on the coast (52 here) and some significant coastal erosion was noted in and south of Pacifica. from 35'+ sea/swells. The sea wall briefly failed near the Pacifica Pier which required emergency repair, and became a national news item. Monterey and zones down to Pt. Conception were also pounded.After this extended shot of rain, skies once again dried out for almost two weeks before a very cold pattern set up with a narrow ridge nosing way up into Alaska forcing GOA lows up into the Arctic before diving straight down the coast. As before, 5 straight days of rain occurred, culminating with the deepest low of four on the 24/25th, bringing 1.6" of precip. Severe  thunderstorms erupted from Monterey south with snow reported below 1000' in the north bay during the potent frontal passage, and pea hail hit Pacifica with sufficient quantity (+ brief 39F temps) to last for several hours on the ground. A particularly nasty front/trough on the 25th pounded  Santa Cruz and Monterey as an intense convective band developed offshore and south of Pacifica then plowed SE down the coast. The cold air. On the 26th, winds turned due North, and one of the heaviest frosts in memory occurred. By months end, skies were once again back into a dry period, but this time a shorter duration of dry is hoped for. However, the cold air does not look like it's going anywhere soon, so even if storminess does resume, the lack of moisture will be of concern. This is historically our "snow window", as many of the rare snow events in the Bay Area seem to come between the 3rd week in January and the second week of Feb. After the dusting we received this month, maybe Feb. has a present for us? 

                   MONTHLY CLIMATOLOGICAL SUMMARY for JAN. 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  54.6  62.7   2:45p  48.1  12:45a   9.6   0.0  0.00   3.8  21.0   8:00a     N
 2  57.9  65.4   3:15p  52.5   6:15a   6.0   0.0  0.00   4.0  15.0  12:45a   WNW
 3  58.1  64.0   2:45p  52.8   4:15a   6.6   0.0  0.00   4.1  22.0  11:00a   WNW
 4  57.9  65.8   3:00p  54.1   2:15a   5.0   0.0  0.00   4.0  18.0   8:45a     N
 5  57.9  65.3   3:45p  51.7   9:00a   6.5   0.0  0.00   3.7  23.0   8:45a     N
 6  53.1  62.7   2:00p  46.9  11:30p  10.2   0.0  0.00   1.0   7.0  12:00p     N
 7  51.9  58.3   2:00p  46.1   3:15a  12.8   0.0  0.10   3.7  43.0   8:45p     S
 8  51.8  55.1  12:45a  48.9  10:45p  13.0   0.0  0.39   4.8  33.0   1:00a     S
 9  49.8  51.6   1:30p  47.5   6:45a  15.5   0.0  0.05   4.6  29.0   6:00p     S
10  53.6  58.2   5:30p  50.7   4:15a  10.5   0.0  0.90  10.4  51.0  12:30p     S
11  49.9  54.7  12:15a  46.5   9:00p  14.4   0.0  1.40   6.9  38.0   9:00a     S
12  51.3  56.9   3:00p  46.0   5:00a  13.5   0.0  0.00   3.6  24.0   5:00a   NNE
13  53.2  56.9   1:15p  50.9  12:00m  11.1   0.0  0.01   2.2  11.0  12:15a   SSW
14  50.4  55.1   1:30p  44.2  11:15p  15.3   0.0  0.00   1.2  10.0   5:30p     N
15  48.2  55.0   2:00p  41.5   7:30a  16.8   0.0  0.00   3.4  24.0   4:00p     N
16  47.2  53.5   3:15p  41.8  12:00m  17.3   0.0  0.00   3.8  22.0  11:30a     N
17  47.0  54.5   2:45p  41.8  12:15a  16.8   0.0  0.00   2.7  16.0  12:45a   NNE
18  48.7  56.0   1:45p  42.2   4:00a  15.9   0.0  0.00   1.2  14.0  10:00a   ENE
19  50.6  57.3   3:15p  46.6   5:30a  13.1   0.0  0.00   2.6  16.0  11:30p     N
20  50.0  59.1   2:45p  45.9  10:00p  12.5   0.0  0.00   3.1  19.0  11:45a     S
21  50.2  56.2   2:30p  44.2   4:15a  14.8   0.0  0.00   2.5  16.0   2:45p    NE
22  51.8  60.4   2:00p  45.1   7:15a  12.3   0.0  0.00   2.3  14.0  10:15p     S
23  51.6  55.5   9:45a  47.0  12:00m  13.8   0.0  0.41   9.1  46.0   7:15p     S
24  47.2  52.5   1:45p  43.2   6:00a  17.2   0.0  0.36   2.1  15.0   5:00p   SSW
25  45.9  50.6  10:45a  41.0   3:15p  19.2   0.0  1.03   6.1  44.0   1:30p     S
26  45.2  49.6   1:45p  41.5  12:15a  19.5   0.0  0.36   3.1  21.0  11:45a   SSW
27  46.3  54.8   2:15p  39.6   2:30a  17.8   0.0  0.01   1.6  14.0  12:00p   WNW
28  48.6  56.9   2:45p  42.3   4:30a  15.4   0.0  0.00   1.7  13.0  11:00a   SSW
29  48.8  54.0   1:00p  42.7  12:00m  16.7   0.0  0.11   3.3  22.0   3:45p    NW
30  46.7  53.5   3:30p  41.9   2:30a  17.3   0.0  0.00   2.6  15.0   4:15p   NNE
31  48.4  57.6   3:30p  43.6   6:30a  14.4   0.0  0.00   3.3  20.0   1:45p   NNE
-------------------------------------------------------------------------------------
    50.8  65.8     4    39.6    27   420.8   0.0  5.13   3.6  51.0    10       N


Max >= 90.0:  0
Max <= 32.0:  0
Min <= 32.0:  0
Min <=  0.0:  0
Max Rain: 1.40 ON  1/11/01
Days of Rain: 10 (>.01 in) 8 (>.1 in) 2 (>1 in)
Heat Base:  65.0  Cool Base:  65.0  Method: (High + Low) / 2