Blythe, in California’s Mojave Desert, had a dew point of 77° during the night of September 7-8 (with the air temperature between 83°-85°).
Dew points for many locations were extraordinarily high for desert locations. Tucson was one of several cities in the Southwest (including Phoenix) that recorded record levels of atmospheric moisture for the month of September this past Monday, as the above graph illustrates. Heavy rainfall also occurred in Tucson where a daily record amount of 1.84” was measured and unfortunately an additional fatality occurred, once again a result of an automobile being swept off a road.
Photo courtesy of Arizona Department of Transportation. Interstate 10 was submerged by the heavy rainfall with one fatality reported south of Phoenix when a car and its occupant were swept down a wash. Map from Flood Control District of Maricopa County. Note the 5.63” in Chandler located at the very bottom right side of the map. Map of rainfall amounts in the greater Phoenix area on September 8th. In fact, it is more than what was measured for the ENTIRE years of 20 when just 2.82” was recorded (Phoenix’s driest years on record). Note that Phoenix’s average annual rainfall is just 8.03”, so the storm dumped approximately 41% of the entire amount of rain that the city normally sees in a year. The top figure was 5.63” at a rain gauge near Alma School in Chandler (an unofficial trained spotter reported 6.09” in northwest Chandler). METARS table from NWS-Phoenix.Įven greater amounts of rainfall were measured in the Phoenix suburbs of Tempe and Chandler just southwest of the airport. As the previous table illustrates this fell short of the September single-hour record of 1.41” that occurred during the storm of September 1939. Note that the greatest single hour of precipitation was 1.02” at the beginning of the storm between 2 a.m.-3 a.m. Hourly METARS at Phoenix Sky Harbor Airport on the morning of September 8th. Table from ‘Climate of Phoenix: NOAA Technical Memorandum NWS WR-177. Sorry this is hard to read: here is the table from the document. Monday’s rainfall was a new 24-hour record for the month of September and the 2nd heaviest such on record.
Record rainfall totals for Phoenix by time period and month since official observations began in 1896 and through 1995. The September 1939 event was similar to yesterday’s (September 8th) in that a dissipating tropical storm over the Eastern Pacific was responsible for the inflow of moisture. However, the 3.29” does rank as the 2nd greatest 24-hour rainfall (beating out 3.06” on September 3-4, 1939). On July 1-2, 1911, 4.98” was measured in one 24-hour period at, what was at that time, the city’s official observation site. Meanwhile, across the country in Virginia, over 12” has fallen near Smithfield in 24 hours.Īlthough the Phoenix total of 3.29” (all of which fell in seven hours between 2 a.m-9 a.m.) was a calendar day rainfall, beating the 2.91” that fell on September 4, 1939, it was not a record 24-hour amount for the city. The official weather site at Phoenix’s Sky Harbor Int’l Airport picked up an all-time calendar day precipitation amount of 3.29”. Moisture associated with former Hurricane Norbert swept over southern California, southern Nevada, and Arizona on Monday resulting in record rainfall for parts of Arizona and flash flooding that took the lives of two.
0 kommentar(er)
