A Red Flag Warning is in effect for portions of the mountains and inland valleys of southern California Sunday night through Tuesday. The forecast calls for gusty northeast winds and low relative humidities. The strongest winds will be Sunday night and Monday with sustained winds of 15 to 30 with gusts up to 50 mph. The lowest humidities will occur Monday. The details vary across southern California — the specifics can be found at the National Weather Service.
The map was current as of 9:20 a.m. PT on Sunday. Red Flag Warnings can change throughout the day as the dozens of National Weather Service offices around the country update and revise their forecasts. For the most current data, visit this NWS site.
On the second day of winter Red Flag Warnings for extreme wildfire danger are affecting portions of Colorado, Nebraska, Kansas, and and New Mexico.
One of the areas affects the Fern Lake Fire in Colorado where the warning will be in effect from noon Sunday until 6 a.m. Monday. The forecast the fire area for Sunday predicts southwest winds of 15 gusting to 24 mph, a high temperature of 51, sky cover of 49 percent, and a minimum relative humidity of 24 percent. However Sunday night will see the winds increasing to a maximum 41 with gusts to 62 along with a 22 percent chance of rain. The humidity will max out Sunday night at 75 percent.
The map was current as of 10:26 a.m. MT on Wednesday. Red Flag Warnings can change throughout the day as the dozens of National Weather Service offices around the country update and revise their forecasts. For the most current data, visit this NWS site.
The map shows Red Flag Warnings in effect for today.
I wonder if the weather forecasters at the National Weather Service realize that when their map shows weather patterns adhering to state boundaries it reduces the credibility of their product. This map brings up some questions… are there really no warnings for Utah, Colorado or western North Dakota? Or, are there really warnings for all of Wyoming and South Dakota? Which portions of the map are accurate?
UPDATE at 9 a.m. September 11, 2012:
I asked Darren R. Clabo, the South Dakota State Fire Meteorologist, for his insight about this issue, and he was kind enough to provide the following:
…It really has to do with the NWS Local Forecast Area boundaries and the boundaries of the individual GACCs.
Here is the link that shows the local NWS office coverage areas as the NWS issues the Red Flag Warning (RFW). Each individual office has the responsibility to issue RFWs for their forecast area. These areas encompass distinct counties, some of which have common borders with other states. Each NWS forecast office does talk to neighboring offices to try to make their forecasts ‘mesh’ but often times, one office will issue a warning while another will not; it all depends on forecaster confidence in the particular weather situation.
It can even get more confusing: The GACCs, in concert with the NWS, determine the criteria for a RFW for their region (due to the different climates within the GACCs). For example, the Rocky Mountain GACC has specific RFW criteria, while the Northern Rockies GACC has a slightly different RFW criteria. If we look at western SD, Harding County typically sees more RFWs than the rest of West River. This is because Harding County is in the Northern Rockies GACC while the rest of SD is in the Rocky Mountain GACC. Furthermore, the GACC boundaries do not correspond to the NWS local office boundaries which contribute to the confusion as well.
Geographic “boundaries” in meteorology always present large hurdles in terms of communicating a forecast, especially when it comes to forecast areas. The zero-order boundaries for RFWs on the map do look goofy but I am not sure how else they could go about it.