WSR-88D Z/R Relationship Table | |||||||
|
This table shows WSR-88D Z/R relationships for sites used in the North Central River Forecast Center Multisensor Precipitation radar mosaic. A Z/R relationship is an empirical formula used to estimate rainfall rates from reflectivity signal strength. Parameters that can be varied at each radar site are shown in red. Max Precip Rate is an adjustable parameter which limits overestimation from hail contamination, ground clutter, etc. The Bias Correction Factor shows three elements: the duration (in hours) used to calculate the bias, the bias (in red), and the number of non-zero gage/radar pairs used to calculate the bias for that duration. Most stratiform rain has a reflectivity signal strength of 20-40dBZ with peaks to 45dBZ, but rarely anything higher (that isn't "brightbanding"). For more information, authorization, instructions, and recommendations regarding Z/R relationships, see the Radar Operations Center's page. | |||||||
| Radar Site | Radar Id | WFO Id | Time Reported (UTC) | Z/R Formula | Max Precip Rate(in/hr) | Z/R Type | Bias Correction Factor |
| Aberdeen, SD | ABR | ABR | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.75 #145 Over-estimation |
| Bethune, SK | XBE | WWG | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 720-hr:1.35 #66 Under-estimation |
| Bismarck, ND | BIS | BIS | 30 Aug 2009 00:00 | Z=300R1.4 | 7.87 | Summer Deep Convection Z/R | 168-hr:0.67 #51 Over-estimation |
| Chicago, IL | LOT | LOT | 30 Aug 2009 00:00 | Z=300R1.4 | 3.44 | Summer Deep Convection Z/R | 168-hr:0.96 #1480 No Bias |
| Des Moines, IA | DMX | DMX | 30 Aug 2009 00:00 | Z=300R1.4 | 5.91 | Summer Deep Convection Z/R | 168-hr:1.07 #2116 Under-estimation |
| Detroit, MI | DTX | DTX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.53 | Summer Deep Convection Z/R | 168-hr:0.79 #402 Over-estimation |
| Dryden, ON | XDR | WTO | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:1.49 #85 Under-estimation |
| Duluth, MN | DLH | DLH | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.87 #602 Over-estimation |
| Exeter, ON | WSO | WTO | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:1.01 #81 No Bias |
| Foxwarren, MB | XFW | WWG | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:1.53 #25 Under-estimation |
| Gaylord/NC Lwr MI | APX | APX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 5-hr:1.90 #21 Under-estimation |
| Grand Rapids, MI | GRR | GRR | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 10-hr:1.10 #25 Under-estimation |
| Green Bay, WI | GRB | GRB | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 1-hr:1.69 #21 Under-estimation |
| Indianapolis, IN | IND | IND | 30 Aug 2009 00:00 | Z=200R1.6 | 4.92 | Marshall/Palmer Stratiform Z/R | 168-hr:0.74 #337 Over-estimation |
| La Crosse, WI | ARX | ARX | 30 Aug 2009 00:00 | Z=300R1.4 | 3.00 | Summer Deep Convection Z/R | 168-hr:0.81 #1127 Over-estimation |
| Lasseteer Lake, ON | XNI | WTO | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:2.23 #164 Under-estimation |
| Lincoln/Ctl Illinois | ILX | ILX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.72 #1560 Over-estimation |
| Marquette, MI | MQT | MQT | 30 Aug 2009 00:00 | Z=130R2 | 4.09 | Cool Season (East) Stratiform Z/R | 2-hr:0.92 #31 Over-estimation |
| Mayville/Grand Forks | MVX | FGF | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.77 #228 Over-estimation |
| Milwaukee, WI | MKX | MKX | 30 Aug 2009 00:00 | Z=300R1.4 | 1.97 | Summer Deep Convection Z/R | 168-hr:1.18 #1359 Under-estimation |
| Minneapolis, MN | MPX | MPX | 30 Aug 2009 00:00 | Z=300R1.4 | 2.78 | Summer Deep Convection Z/R | 168-hr:0.90 #698 Over-estimation |
| Minot AFB, ND | MBX | BIS | 30 Aug 2009 00:00 | Z=300R1.4 | 7.87 | Summer Deep Convection Z/R | 168-hr:0.67 #65 Over-estimation |
| Montreal River, ON | WGJ | WTO | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 10-hr:2.28 #39 Under-estimation |
| North Webster/Nrn IN | IWX | IWX | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:0.77 #1002 Over-estimation |
| Omaha/Valley, NE | OAX | OAX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.92 #665 Over-estimation |
| Owensville, IN | VWX | PAH | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.84 #231 Over-estimation |
| Paducah, KY | PAH | PAH | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.65 #176 Over-estimation |
| Pleasant Hill, MO | EAX | EAX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.66 #330 Over-estimation |
| Quad Cities, IA/IL | DVN | DVN | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.77 #2473 Over-estimation |
| Sioux Falls, SD | FSD | FSD | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.64 #319 Over-estimation |
| Springfield, MO | SGF | SGF | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.74 #181 Over-estimation |
| St. Louis, MO | LSX | LSX | 30 Aug 2009 00:00 | Z=300R1.4 | 4.09 | Summer Deep Convection Z/R | 168-hr:0.65 #713 Over-estimation |
| Woodlands, MB | XWL | WWG | 30 Aug 2009 00:00 | Z=200R1.6 | 4.09 | Marshall/Palmer Stratiform Z/R | 168-hr:1.29 #101 Under-estimation |