I have been amazed by the amount of rainfall falling around here over the past two days, with a number of locations getting the equivalent of an entire September's rainfall in 48hr! Warm, humid, and tropical. At my home in north Seattle I had 1.1 inches the first day and 1.05 inches the second! The ground is saturated.Take a look at the 48-h rainfall analysis from the Seattle Rainwatch web sight (built by the UW and sponsored by the City--Seattle Public Utilities--to allow them to deal with heavy rainfall situations, http://www.atmos.washington.edu/SPU/). Areas from Seattle extending back to Tahoma had over two inches.
Here is a wide view...keep in mind Rainwatch is based on calibrating radar imagery using rain gauges and thus is not useful where terrain blockage is significant (over the Cascades, WA Coast for example). The heaviest rain was apparently near Olympia.
Olympia has accumulated 4.1 inches of rain in just the past 4 days and 5.3 inches over the past 31 days. September normal at Olympia is 2.0 inches for the entire month. Over the past 4 days SeaTac has recorded 3.2 inches of rain, normal for the entire month is 1.7 inches. Want more? For the calendar day yesterday Seattle set a new daily record (.78 inches) ...old record .57 inches in 1983. Want even more? So far this month (ending midnight) Sea Tac has received 3.74 inches, which IS THE WETTEST
18 days on record for September at that location. Olympia has the same claim. The all-time wettest Sept for Sea Tac is 5.95 inches and 7.59 inches for Olympia. A really good chance we will break these records.
If you have a sprinkler system, better turn it off.
I was planning on getting my house painted this fall...I have had second thoughts with all this rain!
Why has it been so wet? For several days we have had a persistent configuration of the upper level flow with a low offshore and southwesterly flow over us and Oregon (it has been even worse down there!). With strong SW flow we have had a warm, moist, unstable air streaming over us for days.
Latest NWS Statement released Monday AM:
835 NOUS46 KSEW 201154
PNSSEW
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
450 AM PDT MON SEP 20 2010
..WET LAST FEW DAYS FOR WESTERN WASHINGTON ESPECIALLY THE PUGET SOUND REGION...
NUMEROUS PRECIPITATION RECORDS WERE SET DURING THE LAST FEW DAYS OVER THE INTERIOR OF WESTERN WASHINGTON.
SEATTLE
THE SEATTLE-TACOMA AIRPORT RAIN TOTAL FOR THE LAST FOUR DAYS WAS 3.23 INCHES ( 0.60 ON THE 16TH...1.49 INCHES ON THE 17TH...0.78 INCHES ON THE 18TH AND 0.36 INCHES ON THE 19TH ). NORMAL FOR THE ENTIRE MONTH OF SEPTEMBER IS 1.63 INCHES SO NEARLY 200 PERCENT OF THE MONTHLY NORMAL WAS RECORDED IN THE LAST FOUR DAYS. 3.23 INCHES WOULD BE THE 12TH WETTEST SEPTEMBER ON RECORD AT SEATTLE-TACOMA AIRPORT IN THE 66 YEARS RECORDS HAVE BEEN KEPT AT THE AIRPORT
( RECORDS STARTED IN 1945 ).
DAILY RAINFALL RECORDS WERE SET ON THE 17TH AND 18TH
17TH 1.49 INCHES...OLD RECORD 1.26 INCHES SET IN 1969
18TH 0.78 INCHES...OLD RECORD 0.57 INCHES SET IN 1983
RECORD ONE HOUR AND TWO HOUR RAINFALL FOR SEPTEMBER WERE SET.
11 PM TO MIDNIGHT ON THE 17TH 0.63 INCHES (OLD RECORD 0.54 9/8/79)
11 PM 17TH TO 1 AM ON THE 18TH 0.94 INCHES (OLD RECORD 0.60 9/22/78)
RECORD THREE DAY SEPTEMBER RAINFALL RECORD WAS SET 16TH THROUGH THE 18TH
2.87 INCHES...OLD RECORD 2.82 INCHES SEPTEMBER 20-22 1972.
RECORD FOUR DAY SEPTEMBER RAINFALL RECORD WAS SET 16TH THROUGH THE 19TH
3.23 INCHES...OLD RECORD 3.10 INCHES SEPTEMBER 19-22 1972
IT WAS THE SECOND WETTEST TWO DAY TOTAL ON THE 17TH AND 18TH...
2.27 INCHES. RECORD 2.36 INCHES SEPTEMBER 22 AND 23 1978.
THE 1.49 INCHES ON SEPTEMBER 17TH WAS THE FOURTH WETTEST SEPTEMBER DAY ON RECORD AT SEATTLE-TACOMA AIRPORT SURPASSED ONLY BY 1.65 INCHES ON SEPTEMBER 22ND 1978 AND SEPTEMBER 30TH 1953 AND 1.51 INCHES ON SEPTEMBER 26TH 1948.
MONTHLY RAINFALL TOTAL THROUGH THE 19TH AT SEATTLE-TACOMA AIRPORT IS 4.10 INCHES. THIS IS CURRENTLY TIED FOR THE FOURTH WETTEST SEPTEMBER ON RECORD. THE RECORD IS 5.95 INCHES SET IN 1978.
TOP 5 WETTEST SEPTEMBERS AT SEATTLE-TACOMA AIRPORT
1. 5.95 INCHES (1978)
2. 5.57 INCHES (1969)
3. 4.60 INCHES (1959)
4. 4.10 INCHES (1972) AND 2010.
THE 4.10 INCHES THROUGH THE 19TH IS THE WETTEST FIRST 19 DAYS OF THE MONTH ON RECORD SURPASSING THE PREVIOUS RECORD OF 3.10 INCHES SET IN 1959.
OLYMPIA
THE OLYMPIA AIRPORT RAIN TOTAL FROM THE 15TH THROUGH THE 18TH WAS 4.09 INCHES ( 0.66 ON THE 15TH...0.91 INCHES ON THE 16TH...1.67 INCHES ON THE 17TH AND 0.85 INCHES ON THE 18TH ). NORMAL FOR THE ENTIRE MONTH OF SEPTEMBER IS 2.03 INCHES SO OVER 200 PERCENT OF THE MONTHLY NORMAL WAS RECORDED BETWEEN THE 15TH AND 18TH. 4.09 INCHES WOULD BE THE 8TH WETTEST SEPTEMBER ON RECORD AT OLYMPIA AIRPORT IN THE 63 YEARS RECORDS HAVE BEEN KEPT AT THE AIRPORT ( RECORDS STARTED IN 1948 ).
DAILY RAINFALL RECORDS WERE SET ON THE 17TH AND 18TH
17TH 1.67 INCHES...OLD RECORD 1.13 INCHES SET IN 1969
18TH 0.85 INCHES...OLD RECORD 0.75 INCHES SET IN 1983
THE 17TH WAS THE WETTEST SEPTEMBER DAY ON RECORD AT OLYMPIA AIRPORT BREAKING THE RECORD OF 1.54 INCHES SET SEPTEMBER 6TH 2009.
RECORD THREE DAY SEPTEMBER RAINFALL RECORD WAS SET 16TH THROUGH THE 18TH
3.43 INCHES...OLD RECORD 3.24 INCHES SEPTEMBER 15TH-17TH 2010. OLD RECORD BEFORE THAT 3.14 INCHES SEPTEMBER 20-22 1972.
RECORD FOUR DAY SEPTEMBER RAINFALL RECORD WAS SET 15TH THROUGH THE 18TH
4.09 INCHES...OLD RECORD 3.54 INCHES SEPTEMBER 20-23 1972
IT WAS THE THIRD WETTEST TWO DAY TOTAL ON THE 16TH AND 17TH...2.58 INCHES. RECORD 2.66 INCHES SEPTEMBER 22 AND 23 1978...SECOND
2.62 INCHES SEPTEMBER 20TH AND 21ST 1972.
MONTHLY RAINFALL TOTAL THROUGH THE 19TH AT OLYMPIA AIRPORT IS 4.95 INCHES. THIS IS CURRENTLY THE FOURTH WETTEST SEPTEMBER ON RECORD. THE RECORD IS 7.95 INCHES SET IN 1978.
TOP 5 WETTEST SEPTEMBERS AT OLYMPIA AIRPORT
1. 7.59 INCHES (1978)
2. 5.23 INCHES (1969)
3. 5.04 INCHES (1972)
4. 4.95 INCHES 2010
5. 4.58 INCHES (1977)
THE 4.10 INCHES THROUGH THE 19TH IS THE WETTEST FIRST 19 DAYS OF THE MONTH ON RECORD SURPASSING THE PREVIOUS RECORD OF 4.00 INCHES SET IN 1978.
$$
FELTON
