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January 2000 Wx Review

Overall, a highly variable month precipitation wise, and moderate temp-wise. Mean temp of 52.1 was just about average, and no real cold outbreaks to speak of. No days of frost were noted here or in the vicinity for the month. January began dry and cool, with no rain for the first 11 days and temps failing to break the 60F mark. However, as the month wore on, the large blocking high of the last 2 months off the cent west coast starting eroding by an increasing series of Pacific impulses, with the first to really break through arriving on the 11th. As the high became further depressed to the south, a dominant GOA low began spinning in regular impulses of energy and drawing moisture up from the tropics. Copius moisture from the SW started flowing onto the cent. west coast along the EPAC high's and GOA low's periphery and by the 18th, a classic (and long lived) pineapple express started to really take shape.  Various parts of the coast from Pt. Concepcion all the way to Washington got hosed on over the next 2 weeks as the narrow rain band worked up and down the coast.. The tropical hose anchored over the Bay Area on the 23/24th, and dropped  5.14" of precip in 48 hrs  in Pacifica. This was the second largest 2 day total in my records, topped only by the 8+ inches in 26 hrs during the record January '84 flood event. Fortunately, the ground was very dry from much below average rains of the last 2 months and little flooding or slides ocurred. By month's end, 9.19" of rain accumulated, well over the normal 5.67". This was the first month in the last three that exceeded monthly norms, and the most significant exceedence since the current 2 year La Nina event began. By months end, a more zonal flow pattern was taking shape, with tails starting to dig ever farther south. With storms starting to trane across the Pacific, the pattern is starting to look a bit more El Nino-ish instead of La Nina.  A continuation of this trend may portend a wet and stormy February.

MONTHLY CLIMATOLOGICAL SUMMARY for JAN. 2000


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  50.3  54.0   3:30p  48.5   7:30a  13.8   0.0  0.00   3.0  18.0   5:00p   SSW
 2  48.7  53.6   1:30p  42.8   8:00a  16.8   0.0  0.00   3.7  19.0  11:00p     N
 3  48.5  57.7   4:00p  42.6   7:00a  14.8   0.0  0.00   1.5  11.0   3:00p    NE
 4  50.2  57.0   4:00p  43.9   5:30a  14.5   0.0  0.03   0.9   7.0   1:00a     N
 5  49.6  56.1   3:30p  44.0   9:30a  15.0   0.0  0.01   1.8  12.0  12:00p     N
 6  50.9  58.5   2:30p  45.8  10:30p  12.8   0.0  0.00   2.5  15.0   5:00a     N
 7  50.0  57.6   3:30p  44.6   9:00a  13.9   0.0  0.00   1.9  10.0   7:00a   WNW
 8  50.8  55.0   3:30p  47.0   8:30a  14.0   0.0  0.02   1.8  12.0   3:30p   SSW
 9  51.2  55.3   3:30p  47.5   3:30a  13.6   0.0  0.00   2.7  14.0   1:00p   SSW
10  52.8  57.3   4:30p  50.3   3:30a  11.2   0.0  0.02   3.0  18.0  11:30p     S
11  51.9  54.7   2:30p  49.0  11:00p  13.2   0.0  0.88   9.4  36.0  12:30p     S
12  48.6  54.3   2:30p  42.7   6:30a  16.5   0.0  0.00   0.8   9.0   2:30p   SSW
13  53.0  55.4   6:30p  49.6  12:30a  12.5   0.0  0.01   5.6  28.0  11:30a     S
14  55.5  62.7   2:30p  52.0   4:00a   7.7   0.0  0.00   1.8  13.0   2:30p   ENE
15  58.7  66.3   3:00p  52.9   7:00a   5.4   0.0  0.03   4.5  31.0  12:00m     S
16  52.6  58.1  12:30a  46.8  11:00p  12.6   0.0  0.95   7.6  43.0   2:00a     S
17  50.3  53.9   4:00p  46.8   3:00a  14.7   0.0  0.08   2.6  15.0   1:30p     W
18  55.6  61.8   4:30p  50.8   1:00a   8.7   0.0  0.90   3.7  26.0  10:00a     N
19  56.5  59.8  10:30a  54.0  12:00m   8.1   0.0  0.31   5.8  31.0   1:00p     S
20  52.2  55.9   2:30p  48.2  10:30p  12.9   0.0  0.01   1.3  10.0   3:00p   SSW
21  52.7  57.5   1:30p  48.9   2:00a  11.8   0.0  0.02   4.1  20.0   4:30p     S
22  53.3  56.5   2:00p  49.9   8:00a  11.8   0.0  0.22   1.6  13.0   9:00p    SW
23  55.4  57.2   2:00p  52.2   1:30a  10.3   0.0  2.42   8.9  41.0   8:00a     S
24  54.4  56.2   6:00a  52.4   8:00p  10.7   0.0  2.72   6.0  38.0   7:00a   SSW
25  52.9  56.3   1:30p  48.8  11:30p  12.5   0.0  0.01   2.1  17.0   6:30p   WNW
26  50.4  55.3   3:30p  46.2  12:00m  14.3   0.0  0.00   2.3  17.0   5:30a     N
27  50.1  58.3   3:30p  45.7   7:00a  13.0   0.0  0.00   1.5  16.0   3:30p     E
28  50.1  56.6   2:30p  45.6   1:30a  13.9   0.0  0.00   2.7  18.0  11:00a   SSE
29  52.3  59.6   3:30p  47.5   8:00a  11.5   0.0  0.00   3.7  18.0   3:30p     S
30  53.2  54.3   8:30a  51.1   9:30p  12.3   0.0  0.49   9.3  42.0   9:30a     S
31  51.1  54.7   2:00p  48.8   7:30a  13.3   0.0  0.06   2.7  20.0   2:00p     N
-------------------------------------------------------------------------------------
    52.1  66.3    15    42.6     3   387.8   0.0  9.19   3.6  43.0    16       S


Max >= 90.0:  0
Max <= 32.0:  0
Min <= 32.0:  0
Min <=  0.0:  0
Max Rain: 2.72 ON  1/24/00
Days of Rain: 15 (>.01 in) 8 (>.1 in) 2 (>1 in)
Heat Base:  65.0  Cool Base:  65.0  Method: (High + Low) / 2