Damp weekend ahead, but the rain is needed

Should there be any doubt that there's an ongoing drought, this graphic illustrates the low streamflows across Virginia as of Thursday:

This is one reason why a forecast for rain this weekend should be welcome, even if it does dampen outdoor plans. Precipitation totals across Mecklenburg County by Monday morning will be in the half-inch to an inch range.

A "cold" front is crossing the Appalachian Mountains this morning and will skid to a stop along the Virginia / North Carolina state line. That nearby boundary will foster showers and a few gusty thunderstorms this Friday afternoon, just after local thermometers top out in the lower 90s. Rain chances will continue until the midnight hour, after which patchy fog is possible atop the wet ground.

Saturday will dawn under mostly cloudy skies with temperatures starting the day near 70º. Additional showers and storms look to hold off until later in the afternoon. Tomorrow's highs will reach the upper 80s accompanied by even stickier air than today's conditions.

Sunday's weather will be similar to tomorrow's, albeit with more peeks of sunshine. Afternoon temperatures and humidity will again mean the sticky upper 80s for highs. Sunday evening the next "cold" front will push through, bringing lower humidity and somewhat cooler air to begin the work week.

Another brief taste of autumn

Mecklenburg County temperatures at this point in September range from morning lows in the mid-60s to afternoon maxima in the mid-80s. Both yesterday and today (Wednesday) the morning lows dipped to near the 60º mark, thanks to drier air and clear skies overnight. The "winner" in this morning's autumn temperature reminder was Clarksville, with 59º registering on a local thermometer.

Unfortunately for cool weather lovers this brief taste of autumn won't last. The high pressure system which brought the lower humidity and temperatures is moving off the coast today, opening the door for warmer and moister air to return. This graphic shows the afternoon highs expected across the lower 48 states today, with the yellow and red shadings indicating above average temperatures:

Locally, highs today will climb back to near the 90º mark under sunny skies. Tonight, thermometers will drop only into the upper 60s thanks to higher humidity holding in the day's warmth. Thursday will then remind folks of August's heat, with afternoon highs reaching the mid-90s along with breezy southwesterly winds.

By Friday afternoon the next cold front will be close enough to trigger showers and storms as the weekend approaches. The next blog post will take a closer look at the overall weekend weather.

Cloudy and damp Sunday, but lower humidity is on the way

Fortunately, Mecklenburg County seems to have escaped damage from Saturday's storms. The "cold" front which oozed through the area at about 5:30 p.m. yesterday fostered some severe weather south of the state line. As of this Sunday morning that boundary is draped across South Carolina and northern Georgia.

The effect of that "cold" front's southern position would normally be clear skies and sunshine locally. However, a few upper air disturbances will swing southeast across the county today. Thus clouds and showers - with perhaps a thunderstorm or two - will dominate local conditions. Temperatures will top out in the low 80s this afternoon.

The good news for the remainder of this week is that dew points will drop as drier air shoves out the jungle-like humidity that has plagued the region. Labor Day itself will finally feature sunny skies, with morning temperatures in the comfortable low 60s and afternoon highs in the mid-80s. Daily highs will slowly climb back into the 90s by Thursday before another cold front pushes through.

Something to note about this week in September is that the average peak of the Atlantic hurricane season arrives. The dotted white line on this graphic represents today's date:

But given the much ballyhooed development of a strong El Nino this year's season looks pretty quiet. Let's hope it stays that way. All it takes is one tropical system to ruin someone's day, week, month, or year.

Holiday weekend outlook: Hot & steamy, then damp and cooler, followed by a nice Labor Day

This Friday morning's low temperature readings of 73º-77º around the county are proof of the sticky humidity levels, since moist air is very efficient in holding the previous day's heat. Another round of upper 90s plus heat indices in the triple digit range will characterize this afternoon, which may also be punctuated by strong to severe storms near or after the 5 o'clock hour. The Storm Prediction Center (SPC) has most of Virginia under a level two out of the five severe weather categories, so keep an eye on the sky.

Tomorrow will also dawn steamy with temperatures a couple degrees lower than this morning. Afternoon highs in the mid-90s will lead to heat index values again at or above 100º ahead of another round of showers and storms. Just like today, on Saturday the SPC is eyeing the region for more severe weather as a backdoor cold front drops south through the Old Dominion. Make sure to heed any weather warnings, sheltering inside a sturdy building to minimize threats from strong winds or lightning.

That boundary will eventually push south of Mecklenburg County Saturday night, with Sunday now looking showery and cloudy. The left panel of this graphic shows the forecast location of the front at 8:00 p.m. Saturday, while the right panel provides the forecast precipitation totals through Monday morning:

Behind this boundary cooler air will hold down Sunday's high temperatures to the mid-80s under mostly cloudy skies. By Monday - Labor Day - that front will have slid far enough south for local skies to clear. Temperatures look to top out in the mid-80s alongside lower humidity for some enjoyable outdoor conditions.

 

Dangerous heat levels through the end of the week

It's still officially summer, but those who might protest that "summer is always hot" are underestimating the heat danger both today - Wednesday - and tomorrow. Afternoon temperatures near the century mark coupled with very sticky humidity levels will yield heat indices (what it feels like) well above 100º both days. Temperatures at dawn won't drop much below the mid-70s, so there won't be much overnight relief.

This combination has prompted the National Weather Service to issue a heat advisory beginning at 11 o'clock this morning and lasting through 8:00 p.m. tomorrow evening.

Although there is a very small chance of showers or storms both evenings, precipitation will remain scanty and scattered until Friday afternoon. By that time a "cold" front will have approached close enough to Mecklenburg County to trigger rain and storms. Until then, expect stifling heat and humidity to blanket the area.

In the meantime, practice heat safety and keep an eye on those most vulnerable to this level of late summer heat. Autumn weather is coming, but it isn't here yet!

Sauna-like conditions begin the work week

Today - Monday, August 31st - is the last official day of meteorological summer, but the weather doesn't pay attention to human definitions. Mecklenburg County will see a resurgence of summertime heat and humidity this week, starting with today's afternoon highs in the mid-90s. The reason for this latest heat wave can be laid at the doorstep of an upper level ridge parked over the eastern half of the nation. 

These ridges feature sinking air underneath them, resulting in generally clear skies and rising temperatures. This graphic showing the upper air flow illustrates this weather feature:

Having said that, there could be a stray shower or storm across the county late this afternoon into the evening. No widespread precipitation is expected, however.

Tuesday looks to be even steamier, with morning temperatures only sagging into the 70s alongside increasing humidity. Tomorrow afternoon local thermometers will climb into the mid-90s to begin the month of September. Again, there is a very slight chance of an afternoon shower or storm tomorrow, but that would be a very localized phenomenon. 

This latest heat wave will continue until a backdoor cold front makes its way south of the area sometime Friday. Until then, the 90s are back in town! 

"False fall" is over and some significant heat is back this week

The pleasantly comfortable conditions of last week (aka "false fall") will be only a memory over the next several days. Heat and humidity are returning with a vengeance Monday. Morning low temperatures look to begin the work week in the sticky low 70s before creeping their way up into the upper 70s by Thursday. Meanwhile, afternoon highs will climb back into the upper 90s and even flirt with the triple digits later in the week.

This graphic shows that this heat is expected to cover the eastern half of the country:

Little or no chance of rain is in the forecast to alleviate the heat through most of the week. Not only will that keep the heat in place, but the continued lack of rain certainly won't help the drought situation!