Robert's Post...

Clouds should begin to depart by this afternoon and remain clear through the day Saturday. Though clear today, expect temperatures to drop as we go through the morning and afternoon. A high of around 61 today has already been met or will be met again late this morning. A stiff Northerly wind will direct cool air into the area with sustained winds of around 15 mph. Saturday should see highs close to 60 with increasing clouds as we move into the overnight. Our next system should bring rain late into the afternoon on Sunday. Forecasted soundings currently show enough surface based CAPE to allow for a few thunderstorms to fire along the boundary. Convection outlook from SPC shows no real confidence, so expect little or no severe criteria to be met Sunday evening.


This morning Matthew and I were discussing the lag temperatures of the seasons and I figured it would make a good blog post. Basically when I say lag I mean the difference in time from solar wattage received and the time that radiation affects local temperatures. With the current solar declination angle, we receive the same amount of watts per meter squared as we do on September 15. The radiation received on a given day based on the sun's angle at a given latitude is known as solar insolation. However, we know that September 15 is much warmer than today with average daily temperatures 20 degrees warmer. This is because of differing heat capacities of the soils, oceans, and air.


Oceans have the highest capacity and air has the least. So the ocean takes longer to heat up and stays warmer longer as well. These lags affect many things beside the gradual warming or cooling of seasons. The local sea breeze on the coast is based on the daily temperature changes of the land along- side the steady ocean temperatures. Thermal differences sets up gradients and creates a local circulation, switching directions from daytime into the overnight (i.e land breeze and sea breeze). Hurricane season is also affected. The peak of hurricane season is in mid September when ocean temps are the highest; yet air temperatures are the highest in late July.


Locally in NC we have varying soil types from rocky, clay, and sandy. In the Piedmont we actually have a trough that sets up quite frequently due to the quick transition from clay soil to sandy soils. In the Summer this actually helps increases thunderstorm potential along this boundaries when instability is high. The higher moisture in clay differs greatly from the sandy soils setting up this local gradient.

Robert Elvington
robert.elvington@gmail.com

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Half and half weekend....

Today will not be a typical temperature day. Most NC Piedmont high temps will occur by around lunchtime today. Look for maybe mid 60s around Charlotte and midday temps near 60 for Triad zones. Temps will then fall through the 50s this afternoon. A little light rain is also possible.

The sky will quickly clear by this evening, and it will be a pretty cold night. Lows tomorrow morning will be in the lower 30s in many spot...even a few upper 20s look possible.

Half and half weekend coming up....look for sunshine tomorrow with highs in the upper 50s to near 60.

Our next system will roll in Sunday and bring some rain back into the region. Still some uncertainty as to how long the rain will hang around, but I will maintain at least some shower chance into Monday as well.

I expect an extended period of mild and dry weather from mid-week into most of the Easter weekend with highs well up into the 70s. I would not be shocked if a few 80 degree reading cropped up by the end of next week.

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Shower chances knocking on the door....

High clouds are increasing and thickening today as our next storm system approaches. There is at least a limited severe weather threat today off to our west, especially in Mississippi and western Alabama, and while we won't see severe weather here, we will see showers as soon as tonight.

Today will be mild and breezy with highs in the lower 70s for most, even mid 70s in the eastern Carolinas. The bulk of the shower activity will be this evening and tonight, but I can't rule out a late-afternoon shower in the western and southern Piedmont.

Shower chances will end for most of us tomorrow morning, and our highs tomorrow will likely occur tomorrow morning with temps falling through the 50s tomorrow afternoon.

Lows Saturday morning will likely be close to the freezing mark in many locations. Highs will warm toward the upper 50s Saturday afternoon with lots of sun.

Our next system quickly rolls in Sunday. Sunday could begin with some drizzle, and rain will arrive as the day unfolds. Whether or not the rain will linger into Monday remains a question mark at this point.

Sunshine will return, along with milder temps, by the middle of next week.

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