Wednesday, October 19, 2011

Cold pattern brings good chance of frost next few mornings

The strong cold front that has been well advertised the last several days made its arrival on Tuesday morning, and its effects did not disappoint! Along with a day of showers, that brought mostly light rainfall amounts, by far the biggest change behind it was the dramatic drop in temperatures. After a near-record high of 86 degrees on both Sunday and Monday, readings plummeted into the 40s by Tuesday afternoon, a near 40-degree drop! With gusty north winds, for the first time of the fall season, wind chill values were being calculated across the Mid-South! Temperatures have remained quite cool for Wednesday, as we've struggled to climb into the 50s with clouds that have moved in behind the low pressure area associated with Tuesday’s cold front. These clouds will begin clearing tonight, as high pressure moves closer to the region, and this will make for a few even colder nights to come, including the good chance of some frost for parts of the metro.

Once clouds clear this evening, temperatures should fall rather steadily overnight across the area. While the center city of Memphis will likely hover closer to 40 degrees, the suburbs and outlying areas will see temperatures dip into the upper 30s. While some patchy frost is a possibility for the coldest areas and in sheltered locations, wind speeds of 5-10mph will likely preclude the development of widespread frost.

A much better chance of frost appears to be setting up for Thursday night into Friday morning, as high pressure moves overhead. This will allow for winds to become light to calm, and with clear skies, optimal radiational cooling is expected. Minimum temperatures in the mid to upper 30s are expected, and areas of frost are quite likely for much of the metro by Friday morning, with perhaps just the city limits of Memphis warm enough to prevent much frost from forming.

NWS surface weather map forecast for Friday morning, showing the Canadian high pressure area directly over the region, which will enhance the chance of frost formation for much of the metro area.

A final, lesser chance of frost may occur Friday night into Saturday morning. Temperatures will be a bit milder as southerly wind flow begins to return, but winds may be light enough, along with continued clear skies, to allow a few readings in the upper 30s in the outlying areas that could promote some additional patchy frost in these areas.

If you have sensitive plants, it may be a good idea to cover or bring them indoors the next few nights to prevent damage. After Saturday morning, the threat of frost will be ending, for at least a little while. The weather pattern will be moderating under the returning southerly wind flow, with temperatures back to average levels, if not a bit above, by early next week. However, another front may bring rain chances for the middle of the week, and some long-range models are indicating another blast of cold air could follow. We’ll be tracking that possibility closely next week!

Stay tuned to MemphisWeather.Net for the latest on the possibility of frost, including any formal frost advisories that may later be issued by the National Weather Service office in Memphis.

--Kevin Terry, MemphisWeather.Net

----
For weather information for Memphis and the Mid-South, where and when you need it, visit MemphisWeather.net on the web, m.memphisweather.net on your mobile phone, download our iPhone or Android apps, or visit us on Facebook or Twitter.

No comments: