Robert J. Renard, Volunteer Observer
Nat'l Wea Serv Climatological Station Monterey, California 93940
SUMMARY OF THE MAY 1996 WEATHER ON THE MONTEREY PENINSULA, CALIFORNIA
General: This May's rainfall and average temperatures were well above
normal, while winds and number of fog days were near seasonal values.
There was considerable variation day-to-day and week-to-week for all of
the weather elements..
Temperature: Yes, one more month of above normal temperatures -- eleven
consecutive to be exact! And the fifteenth above normal month in the
last seventeen! Although thirteen May days were below normal, the
relatively high positive anomaly on many of the eighteen above normal
days ruled the month in the averages.
The daytime maximums averaged 68.5F (64.5F is normal) -- the fourth
highest in at least 45 years, while the nitetime minimums averaged 49.2F
(48.0F is normal) -- the fifth warmest in at least 45 years. Overall,
the average of 58.9F is 2.7F above normal. With nine of the last
eleven May days below normal, along with cool gusty winds, the early and
mid-month "heat waves" seemed to be forgotten by month's end..
A number of daily temperature records were set this past May -- all
on the warm side. The nite-time minimums from 15-18 May 1996 are new
records:
15 May 57F topped 56F, 1970
16 May 58F topped 55F, 1970
17 May 57F topped 53F, 1957
18 May 57F topped 56F, 1992
As for the maximums: On 1 May the 87F high was well above the
previous record of 79F, set in 1970, and the 89F maximum on 11 May was
10F above the previous record set in 1981.
Although the date of "last frost" at this station averages 17 March
and the latest date on record with frost is 4 May (6 March this year),
several nearby valley sites reported frost as late as 10 May this year,
namely Carmel Valley Village area and San Benancio Canyon several miles
inland from Highway 68.
Precipitation: Rainfall continued to defy expectation this rain year.
The May total of 1.33" classifies the month's rainfall as very heavy.
0.46" is the normal and only two May's in the last 45 years recorded
rainfall higher than this year: 2.39" in 1957 and 1.83" in 1990.
Boosted considerably by the 8.08" in February this year, the rain-year
total stands at 20.90" vs. 18.72" normal. Normal for the rain-year
(1 July thru 30 June), based on 45 years of data, is 18.94". Expectations
for June is only 0.22". June is normally the year's third driest month.
The most significant rain of May 1996 was the 0.97" in the 24-h
period 6 PM 15 to 16 May. The 0.97" is the second highest one-day May
rainfall in at least 45-years. Power outages on the evening of the 15th
and damage to regional crops production, like lettuce and strawberries,
was related to the heavy rains.
This year's total of at least 20.90" assures three out of the last
four years with above normal rainfall -- a very uncommon event! It
happened only one other four-year period in the last 45 years, namely
rain years 1979-1980 through 1982-1983. Total rainfall for the four
rain years ending 30 June 1996 is 93.51" (so far!), while the four-year
total for rain years 1979-1980 through 1982-1983 is 109.59".
Wind: 7.3 miles per hour (mph) is the average Airport wind (6 AM to 11 PM)
for this past May, which is close to the five-year average of 7.7 mph.
Gust information from the National Weather Service Climate Station is only
available through 19 May (equipment failure after that date). In that
period the highest measured gust was 35 mph on 16 May, however gusts
estimated to be in the range 30-40+ mph occurred on the afternoons of 20,
22, 23 (especially high), 24, and 25 May.
Fog: The number of fog days returned to normal (= 14) this past month,
after only four fog days in April (normal = 8). Only four months (April
1996, September 1995, July 1995, October 1994) are associated with a
sub-normal number of fog days in the last 23 months.
Earthquake: A light earthquake (centered 10 miles east of San Jose) was
felt by some residents on the Monterey Peninsula (including at this
Station) about 1:52 PM PDT on 21 May 1996.
Comparative Weather Data
for Stations on/near the Monterey Peninsula and Salinas
May 1996
Following are comparative figures from seven local observation sites:
1) the National Weather Service Climate Station (NWSCS), (elevation 385')
located in the western hilly section of Monterey; 2) the National Weather
Service Forecast Office (NWSFO) site (elevation 122'), located in the flat
area of eastern Monterey, on the NPS Annex grounds adjacent to Airport;
3) the Naval Postgraduate School Campus (NPS), Monterey; 4) the Ft.Ord
site (Ft. Ord (NPS)) (elevation 167') located just northwest of Marina
Municipal Airport (formerly Fritschie Field). This is the site of the
Naval Postgraduate School's wind profiler (managed by the Department of
Meteorology); 5) Site SE end of Marina, located about 2 « miles ESE of
Monterey Bay (elevation 80'); 6) Carmel Valley site (CV) near Village
(elevation 500'); south facing slope; 7) SW Salinas (SAL) vicinity of W.
Blanco Rd. within « mile of S. Main St.
Location Temperature (F) Precipitation Wind
Avg. Highest Avg. Lowest (inches) (mph)
Max. Min. May this yr "Norm" Max Ave
(1 Jul-31 May)
1) NWSCS:
68.5 89 49.2 44 a1.33 20.90 18.72@ 35** --
-----------------------------------------------------------------------------
2) NWSFO:
69.7 86 50.3 43 b1.30 16.92 -- -- 7.3*
-----------------------------------------------------------------------------
3) NPS:
68.0 80 49.9 43 c1.21 18.18 15.12# -- --
-----------------------------------------------------------------------------
4) Ft. Ord (NPS):
65.6 87 47.4 40 d1.08 12.38 -- 25 10.3
-----------------------------------------------------------------------------
5) Marina:
68.2 86 49.4 41 e1.33 14.44 15.15& -- --
-----------------------------------------------------------------------------
6) CV:
76.4 95 44.2 36 f2.26 18.98 17.92# -- --
-----------------------------------------------------------------------------
7) SAL:
77.3 93 48.3 39 g1.09 14.53 13.20%est. -- --
-----------------------------------------------------------------------------
FOOTNOTES:
observations for precipitation:
a,e = 6 PM b,d = midnight c = 4 PM f, g = 8 AM
(NOTE: for f, g: 24-h rainfall measured 8 AM, first day of the month
counts for previous month)
* = average hourly Airport winds in period 6 AM to 11 PM.
@ = 45-year average # = 39-year average % = 10-year average
& = 12-year average ** = from wind gust data through 19 May only
90-Day Temperature and Precipitation Outlook for the Central Coast:
National Weather Service 90-day outlook for June through August indicates
a continuation of above normal temperatures, with rainfall more likely
near normal than significantly above/below normal. Following normals are
for the National Weather Service Climate Station (45-year data base).
Rainfall Normal Max/Min Temps
June 0.22" June 67.0/50.2
July 0.07" July 68.1/51.8
August 0.10" August 69.3/52.3