BLOG: St. Patrick’s Day
It is warming back to near 70 degrees Saturday. However there is some moisture in the lower levels of the atmosphere. That will result in areas of low clouds and fog for a time in the morning, and then those clouds and fog can return again in the night and last into Sunday morning. Also, with the new high building over the Atlantic, there may be more of a flow from the ocean that keeps clouds longer Sunday and trims temperatures down to the middle 60s. We may have the low clouds and fog filling back in Sunday night into Monday morning as well.
This moisture being caught under an inversion with a weak flow can be common when high pressure in the western Atlantic has a weak flow from the ocean directed across our area and the upper levels of the atmosphere are warmer than the air below. The air near the ground cools at night, and if enough moisture is present, that moisture condenses into clouds or clouds and fog, and then we have to wait for the heating of the day to mix this moist layer out and have more in the way of sunshine. This will probably help keep high temperatures from reaching their full potential, but they will be fairly comfortable for March and well above average the next few days.
We will be dry through Sunday night, and then on Monday all of the models have a piece of energy that comes eastward and could help trigger a shower Monday afternoon. The models all have different solutions on how to handle this bundle of energy and where and to what extent it will get trapped in the upper level ridge. For now we have the chance of a shower Monday afternoon, and we also allow a shower or thunderstorm Tuesday and Wednesday. Certainly not a wash out if it happens, but just not sure at this point we have all dry weather across all of the area Monday afternoon through Wednesday. Again, just chance material for now, and it will be warmer than average with dry weather most of the time.