|Dew Point:||60.9°F (16.1°C)|
|Wind:||From the SW at 2.0 MPH Gusting to 4.0 MPH|
|Sea Level Pressure:||25.39" (859.7 mb)|
Scattered Showers And ThunderstormsHigh: 78 Low: 65
Showers And ThunderstormsHigh: 71 Low: 57
Rain Showers LikelyHigh: 64 Low: 51
SunnyHigh: 66 Low: 53
SunnyHigh: 70 Low: 57
Scattered showers and thunderstorms. Mostly cloudy, with a high near 78. West wind around 8 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.
Scattered showers and thunderstorms before 1am, then a chance of showers and thunderstorms. Mostly cloudy, with a low around 65. West wind around 9 mph. Chance of precipitation is 50%. New rainfall amounts between a tenth and quarter of an inch possible.
A chance of rain showers before 8am, then showers and thunderstorms. Mostly cloudy, with a high near 71. West wind around 12 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Showers and thunderstorms. Cloudy, with a low around 57. Northwest wind around 10 mph. Chance of precipitation is 90%. New rainfall amounts between three quarters and one inch possible.
Rain showers likely. Mostly cloudy, with a high near 64. North wind 6 to 9 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
A slight chance of rain showers before 9pm. Partly cloudy, with a low around 51. Chance of precipitation is 20%.
Sunny, with a high near 66.
Mostly clear, with a low around 53.
Sunny, with a high near 70.
... Scattered storms, humid, though slightly less hot today. More storms tomorrow with a cold front crossing by Monday night. Cooler, drier weather to follow this week with large high.
NEAR TERM /THROUGH MONDAY/... As of 230 PM Sunday...
A major pattern shift gets underway through the period as a Canadian trough gains strength and descends into the Great Lakes region. The first in a series of associated shortwave troughs drops into the upper Mississippi Valley/upper Great Lakes today and tomorrow, slowly pushing a surface front to the Middle Ohio Valley by the end of the period Monday evening. Ahead of the front, gradually increasing mid-level and eventually deep-layer flow increases baroclinicity, providing a ripe environment for mesoscale-driven rounds of showers and storms throughout the period.
Today, instability has grown to 2-3k J/kg MLCAPE with the hot and humid environment. This along with relatively weak wind fields, some mid-level dry-air, and PWATS approaching 1.8-2", yields quickly- developing pulsating storms capable of producing strong wind gusts, isolated damaging especially in the Ohio Valley. Along with precipitation loading, high moisture content promotes heavy rain with has led to at least isolated flash flooding, particularly along slow-moving remnant outflow boundaries where convective initiation prefers this afternoon. Due to meso-forced nature of PoPs today, have painted a fairly broad brush of scattered storms with cumulus fields basically everywhere.
Tonight, convection dies down with the setting sun, approximately 00- 03Z. Aside from lingering showers from daytime convection, have maintained at least an isolated possibility of a shower or storm overnight with nearly saturated profiles and tall/skinny CAPE suggesting any blip of forcing in the atmosphere will be capable of producing precipitation, mainly along any old outflow boundary remaining overnight. Additionally an MCS developing presently in Illinois could track all the way into the Ohio Valley overnight as it weakens.
As the sun rises tomorrow, widespread coverage of showers and storms returns through the morning and afternoon. Saturated profiles tomorrow limit explosive convective development, however high moisture availability leaves at least a marginal risk for damaging wind gusts. Mid-level wind fields increase nearly parallel to the cold front as the base of the mid-level trough enters from the NW by mid-Monday, which provides strong, moist, backbuilding inflow that will lead to multiple rounds of possibly training rain and storms. Had toyed with a flash flood watch, and think that one may be needed at some point, however dry conditions as of late, ongoing scattered convection today, and low confidence in heavy rain corridors tomorrow doesn't provide enough confidence to geographically place a FFW. Will leave this to subsequent shifts to decide. Widespread rain and thick clouds will limit temperatures to the 70's and low-80's tomorrow.
SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... As of 425 PM Sunday...
This period brings relief from the heat in ernest, as a cold front crosses Monday night, in response to a long wave pattern change. A long wave trough, already having dug in by Monday night, amplifies over the eastern U.S. through Tuesday.
A short wave acting to carve out the deeper long wave trough as it rotates through it, drives the surface cold front from the middle Ohio Valley through the central Appalachians Monday night. The back edge of showers and thunderstorms along and ahead of the front push south and east of the Ohio River Monday night, and then through the central appalchians by about dawn Monday.
Instability will be limited to very narrow CAPE early on ahead of the front, given lack of diurnal heating because of clouds and showers and thunderstorms in the area on Monday with the front and short wave trough. High PW values, ahead of the front, and high coverage of rainfall leading into Monday night may still present a flash flood threat, prior to and shortly after the front crossing. Models are less wavy with the front then previous runs, and any instability and the high moisture content wane quickly as the front pushes through.
Stratus and some fog are likely to set in by Tuesday morning, as significantly cooler air behind the front arrives. Any fog will burn off quickly Tuesday morning, and the stratus will mix into morning stratocu, and then an afternoon cu field, as the mixing layer deepens.
Valley fog is likely to form Tuesday night give wet conditions, if the pressure gradient ahead of high pressure still out over the midwest, becomes weak enough to allow decoupling. High pressure overhead Thursday morning spells valley fog once again even with another day of drying, as fog season looms near. In the much cooler air, steam fog is likely to form along the rivers both Tuesday and Wednesday nights.
No major adjustments to central guidance temperatures and dew points which depicts the much cooler weather in the wake of the cold front.
LONG TERM /THURSDAY THROUGH SUNDAY/... As of 425 PM Sunday...
High pressure at the surface and slowly building through the upper levels spells a period of dry weather, with temperatures slowly moderating back to normal for mid summer. Valley fog may become less prominent with each night. Good hay stretch upcoming.