Monthly Precipitation Probabilities and Quintiles

Transcription

1 CLIMATOGRAPHY OF THE UNITED STATES NO. 81 Supplement No. 1 Monthly Precipitation Probabilities and Quintiles NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION NATIONAL ENVIRONMENTAL SATELLITE, DATA, AND INFORMATION SERVICE NATIONAL CLIMATIC DATA CENTER ASHEVILLE, NC

2 NOTES Page 2 Product Description: This Climatography includes selected precipitation probabilities derived from the normals. Precipitation quintiles, divided into six classes by the five probability levels 0.2, 0.4, 0.6, and 0.8, are also provided. Precipitation probabilities at the 0.1, 0.5, and 0.9 levels are also presented. This publication includes precipitation probabilities and quintiles for first-order stations; all other stations are available through an accompanying digital data set associated with Climatography of the United States, No. 81. The precipitation probabilities are the monthly precipitation totals that correspond to the indicated probability levels. The probability levels are based on the historical sequential monthly precipitation. The historical precipitation data are the adjusted values from the monthly normals as presented in Climatography of the United States No. 81. Abbreviations: = Description of Station Line 1: COOP ID = Cooperative Network ID (1:2=State ID, 3:6=Station Index), Call = 3-Letter Station Call Sign for First-Order Stations Line 2: Station Name Line 3: State 2-Letter Postal Abbreviation (e.g., AL for Alabama) Quin = Maximum Value for Quintile Range (e.g., Q1 provides maximum value for 0-20% quintile range); Q0 provides minimum value. Prob = Selected Probability Level Jan, Feb, Mar,, Oct, Nov, Dec, ANN = Monthly and annual precipitation probability values (to hundredths of an inch of precipitation) Computational Procedures: When historical climate data are accumulated and examined, they generally follow a certain pattern called a statistical distribution. While temperature usually follows a Gaussian or bell-shaped distribution, precipitation does not because it is zero-bounded. Precipitation generally follows a Gamma distribution, where most values are near zero with rapidly diminishing higher values. Thus, the Gamma distribution was used to estimate the precipitation probability and quintile statistics. Probabilities are computed for the amount of precipitation expected at fifteen probability levels (0.005, 0.01, 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, 0.95, 0.99, and 0.995) for each month of the year and for the annual total. For example, if 1.77 inches corresponds to the 0.20 probability level, that means that on average, 2 out of 10 years will have 1.77 inches or less of precipitation in that month. It also means that, on average, 8 out of 10 years will have more than 1.77 inches of precipitation in that month. A selection from these 15 probability levels are included in this publication. The precipitation quintiles show the expected precipitation values at the five quintile levels shown for each of the twelve months: 1. First Quintile (0-20%); 2. Second Quintile (20-40%); 3. Third Quintile (40-60%); 4. Fourth Quintile (60-80%); 5. Fifth Quintile (80-100%). For example, if 2.91 and 4.07 inches are the bounds for the second quintile (level 2), then a monthly total precipitation amount for that month falling in the range 2.91 to 4.07 would be classified as a second quintile precipitation amount and that month would be considered relatively dry. The first line (Q0) shows the minimum precipitation value derived from the historical record. This would be used if a future precipitation observation is less than the minimum. At the opposite end, Quintile level 5 (indicated with Q5) would be used if the observed value is more than the maximum. Missing Values Missing values are indicated with a References: Crutcher, H.L., G.F. McKay, and D.C. Fulbright, 1977: A note on a gamma distribution computer program and computer produced graphs, NOAA Technical Report EDS 24. Crutcher, H.L. and R.L. Joiner, 1978: Gamma distribution bias and confidence limits, NOAA Technical Report EDIS 30. Release Date: June 20, 2002 National Climatic Data Center/NESDIS/NOAA, Asheville, North Carolina

3 Page ANB Q0 MIN ANNISTON METRO AP AL Q Q Q Q Q5 MAX BHM Q0 MIN BIRMINGHAM INTL AP AL Q Q Q Q Q5 MAX HSV Q0 MIN HUNTSVILLE INTL AP AL Q Q Q Q Q5 MAX MOB Q0 MIN MOBILE RGNL AP AL Q Q Q Q Q5 MAX MGM Q0 MIN MONTGOMERY DANNELLY AP AL Q Q Q Q Q5 MAX MSL Q0 MIN MUSCLE SHOALS AP AL Q Q Q Q Q5 MAX TCL Q0 MIN TUSCALOOSA ACFD AL Q Q Q Q Q5 MAX DVT Q0 MIN DEER VALLEY (PHOENIX) AZ Q Q Q Q Q5 MAX

4 Page DUG Q0 MIN DOUGLAS BISBEE INTL AP AZ Q Q Q Q Q5 MAX FLG Q0 MIN FLAGSTAFF PULLIAM AP AZ Q Q Q Q Q5 MAX PHX Q0 MIN PHOENIX SKY HRBR INTL A AZ Q Q Q Q Q5 MAX SAD Q0 MIN SAFFORD AGRICULTRL CTR AZ Q Q Q Q Q5 MAX TUS Q0 MIN TUCSON INTL AP AZ Q Q Q Q Q5 MAX INW Q0 MIN WINSLOW AP AZ Q Q Q Q Q5 MAX ELD Q0 MIN EL DORADO S AZ RGNL AP AR Q Q Q Q Q5 MAX FYV Q0 MIN FAYETTEVILLE EXP STN AR Q Q Q Q Q5 MAX

5 Page FSM Q0 MIN FORT SMITH RGNL AP AR Q Q Q Q Q5 MAX HRO Q0 MIN HARRISON BOONE CO AP AR Q Q Q Q Q5 MAX LIT Q0 MIN LITTLE ROCK ADAMS AP AR Q Q Q Q Q5 MAX FUL Q0 MIN ANAHEIM CA Q Q Q Q Q5 MAX BFL Q0 MIN BAKERSFIELD KERN CO AP CA Q Q Q Q Q5 MAX BIH Q0 MIN BISHOP AP CA Q Q Q Q Q5 MAX BLU Q0 MIN BLUE CANYON CA Q Q Q Q Q5 MAX BLH Q0 MIN BLYTHE AP CA Q Q Q Q Q5 MAX

6 Page BUR Q0 MIN BURBANK VALLEY PUMP PLN CA Q Q Q Q Q5 MAX CZZ Q0 MIN CAMPO CA Q Q Q Q Q5 MAX CEC Q0 MIN CRESCENT CITY 3 NNW CA Q Q Q Q Q5 MAX DAG Q0 MIN DAGGETT BARSTOW AP CA Q Q Q Q Q5 MAX ONT Q0 MIN FONTANA KAISER (ONTARIO CA Q Q Q Q Q5 MAX FAT Q0 MIN FRESNO YOSEMITE INTL CA Q Q Q Q Q5 MAX IPL Q0 MIN IMPERIAL CA Q Q Q Q Q5 MAX WJF Q0 MIN LANCASTER ATC CA Q Q Q Q Q5 MAX

7 Page LGB Q0 MIN LONG BEACH AP CA Q Q Q Q Q5 MAX LAX Q0 MIN LOS ANGELES INTL AP CA Q Q Q Q Q5 MAX CQT Q0 MIN LOS ANGELES DOWNTOWN US CA Q Q Q Q Q5 MAX MOD Q0 MIN MODESTO CITY-COUNTY AP CA Q Q Q Q Q5 MAX MRY Q0 MIN MONTEREY CA Q Q Q Q Q5 MAX Q Q0 MIN MORRO BAY FIRE DEPT CA Q Q Q Q Q5 MAX MHS Q0 MIN MOUNT SHASTA CA Q Q Q Q Q5 MAX EED Q0 MIN NEEDLES AP CA Q Q Q Q Q5 MAX

8 Page OAK Q0 MIN NEWARK (OAKLAND) CA Q Q Q Q Q5 MAX CMA Q0 MIN OXNARD (CAMARILLO) CA Q Q Q Q Q5 MAX PSP Q0 MIN PALM SPRINGS CA Q Q Q Q Q5 MAX PRB Q0 MIN PASO ROBLES MUNICIPAL A CA Q Q Q Q Q5 MAX RBL Q0 MIN RED BLUFF AP CA Q Q Q Q Q5 MAX RDD Q0 MIN REDDING MUNICIPAL AP CA Q Q Q Q Q5 MAX SAC Q0 MIN SACRAMENTO AP CA Q Q Q Q Q5 MAX SNS Q0 MIN SALINAS AP CA Q Q Q Q Q5 MAX

9 Page SDB Q0 MIN SANDBERG CA Q Q Q Q Q5 MAX SAN Q0 MIN SAN DIEGO LINDBERGH AP CA Q Q Q Q Q5 MAX SFO Q0 MIN SAN FRANCISCO INTL AP CA Q Q Q Q Q5 MAX SBA Q0 MIN SANTA BARBARA MNCPL AP CA Q Q Q Q Q5 MAX SMX Q0 MIN SANTA MARIA AP CA Q Q Q Q Q5 MAX SCK Q0 MIN STOCKTON AP CA Q Q Q Q Q5 MAX TRM Q0 MIN THERMAL RGNL AP CA Q Q Q Q Q5 MAX UKI Q0 MIN UKIAH CA Q Q Q Q Q5 MAX

10 Page WVI Q0 MIN WATSONVILLE WATERWORKS CA Q Q Q Q Q5 MAX SIY Q0 MIN YREKA SISKIYOU CO CA Q Q Q Q Q5 MAX AKO Q0 MIN AKRON 1 N CO Q Q Q Q Q5 MAX ALS Q0 MIN ALAMOSA BERGMAN FIELD CO Q Q Q Q Q5 MAX COS Q0 MIN COLORADO SPRINGS MNPL A CO Q Q Q Q Q5 MAX DEN Q0 MIN DENVER INTL AP CO Q Q Q Q Q5 MAX GJT Q0 MIN GRAND JUNCTION WALKER A CO Q Q Q Q Q5 MAX LHX Q0 MIN LA JUNTA 4 NNE CO Q Q Q Q Q5 MAX

11 Page LXV Q0 MIN LEADVILLE 2 SW CO Q Q Q Q Q5 MAX LIC Q0 MIN LIMON CO Q Q Q Q Q5 MAX PUB Q0 MIN PUEBLO AP CO Q Q Q Q Q5 MAX BDR Q0 MIN BRIDGEPORT SIKORSKY AP CT Q Q Q Q Q5 MAX BDL Q0 MIN HARTFORD BRADLEY INTL A CT Q Q Q Q Q5 MAX MMK Q0 MIN MIDDLETOWN 4 W (MERIDEN CT Q Q Q Q Q5 MAX ILG Q0 MIN WILMINGTON NEW CASTLE A DE Q Q Q Q Q5 MAX AAF Q0 MIN APALACHICOLA AP FL Q Q Q Q Q5 MAX