Photo by Runs with Scissors on Flickr

The low temperature this morning was 85 degrees. Care to guess what the normal high is for today? Climatologically, July 20-22 are the warmest days of the year, with average highs of 85 and lows of 70. Today will be about 15 degrees warmer than that. The humidity will drop a bit this afternoon, allowing the temperature to approach the record of 101 degrees under hazy smurf-blue skies. After another very warm night tomorrow's high will again approach the triple digits. Be careful everyone! There's a very slight chance of afternoon showers on Saturday.

Relief from the heat will occur sometime on Sunday. A slow-moving cold front could pass through the area as early as early Sunday morning. That might kick off a few showers or thunderstorms and Sunday's high will be only around 90. Break out the parkas, Monday is likely to be cooler than normal with a high only in the lower 80s as the front edge of a cooler air mass finally arrives.

After reading about heat domes yesterday we got curious about the term as it is not one that meteorologists use. A heat dome appears to be the jargon-free description of a summertime ridge of high pressure. A quick LexisNexis search says the phrase has been used 263 times since 1983. The first use in the manner it is being bandied about this week was by Kevin Myatt in his Weather Journal column in the Roanoke Times on 8 May 2004. Myatt has used the phrase consitently over the past seven years, but other than him the phrase didn't get used often in a meteorological sense until the Canwest News Service started using it on Saturday and the AP picked up the term this past Monday. In the past week "heat dome" has appeared 116 times, including four times yesterday on Gothamist.