Sometime this evening they cancelled the Red Flag Fire Warning, so I'm bumping this down the page.

Carol, They base the warnings on a combination of wind speed, humidity and temperature. I am sure the dryness of the vegetation must factor into it somehow. Y'all are lucky to be getting rain as so much of the state is not. Today's biggest problem likely is the Relative Humidity. Our RH is very low. Our mesonet station is down, so I can't say for sure how low, but when I checked a few seconds ago, the Mesonet station nearest us was showing 14% and the nearest station on the Texas side of the river is showing 7%. Tim has been outside mowing and has been saying for hours he thinks our RH is in the single digits. To me it feels more like 12 to 14%. It wouldn't surprise me to have Red Flag Fire Warnings or Fire Weather Watches up for parts of the state every day for the next few days. The current conditions are very similar to, but perhaps drier than, the conditions in April 2009, in many parts of the state. The amount of recent rain that has fallen is not that relevant to fire danger until your dormant vegetation has been replaced with fresh, green vegetation. In an an area with a KBDI of 600 or higher, recent rain makes little difference as long as the KBDI is that high. In an area like ours with clay soil, heavy rain can make it harder to fight fires. If fires occur before significant greenup occurs, then the dead vegetation still burns and the firetrucks can't get out into the fields to fight it because they get stuck in the mud. Our KBDI is relatively low here, so the one fire we've had here today moved slowly in a field that was about half greened-up. Another couple of weeks and fires will be much less likely here in our county. Our relative greenness when I checked it yesterday was 58% so we have a lot more green than we had a couple of weeks ago. In past droughty springs, we've been to fires in fields that look totally green and quite lush. However, there was such a thick layer of thatch and dormant vegetation from previous years (esp. in pastures that are never mowed and never grazed) lying on the ground that it was burning underneath the green grass. I've been outside most of the day and my skin is so dry I don't even really know how to describe it. My hands feel like sandpaper and my skin hurts. Now that I'm inside, I'm going to slather on the hand lotion. Dawn

Oops. Forgot the link. Here is a link that might be useful: Webpage of Norman office of the NWS

This warning has expired.