Aikyam-Lab/Synoptic-Bench huggingface dataset:
A trailing upper level low, currently located over the Quad Cities area, will slowly drift east-southeastward through the area over the next 24-36 hours, keeping widespread cloud cover over the area into Saturday as well as chances for showers over much of the area tonight and across eastern portions of the area on Saturday as energy pivots around the upper low. Will likely pull any thunder mention after 00Z as forecast profiles show nearly zero instability, even elevated, which fits with a lack of any significant convection associated with the upper low itself so far. Slow progression of the upper low will merit maintaining pops across the eastern third to half on Saturday, however, gradually tapering off by evening, with dry weather and mostly clear skies returning for Saturday night.
Later this evening more showers are possible ahead of cold front now moving across western Tennessee. Temperatures will be about 15 degrees cooler.
Our cold front has stalled along the Pecos river and nearly all TAF sites remain with winds out E. Currently, a cold front is moving southwest across the area with the front expected to hang up around the Pecos River later this morning. This includes near the Stockton Plateau, along the dryline in SE NM, and then along the lifting warm front in the Permian Basin.
Elsewhere, expect warm temperatures to generate cumulus over the higher terrain with a few showers over the San Juan mountains. Slightly cooler temperatures are expected behind the trough passage for Saturday. Model consensus shows a weak trough will develop over Baja California on Saturday. The circulation around this trough will combine with an increasingly moist flow from the southeast across the Continental Divide by late Saturday.
A thin line of weakly forced showers have begun to redevelop ahead of a cold front which is positioned nearly parallel with the Lower Mississippi River. A deck of low clouds have slowed surface heating across the northern portions of the forecast area, but temperatures have still managed to reach the lower 80s while greater amounts of sunshine and less cloud cover in the south has resulted in mid/upper 80s. Much cooler and drier air will follow behind and conditions on Saturday will be seasonably pleasant with a northwesterly breeze. Look for partly cloudy skies with lows in the 50s north to mid 60s south with highs in the lower 70s north to lower 80s south.
Early this afternoon, a weak cold front was situated from Sterling county, southeast through central Coke county, and then east across northern Brown county. Saturday will be cooler, with some lingering showers over eastern sections during the morning hours. Lows tonight will be in the 60s, with highs Saturday ranging from the upper 70s north, to the lower 80s south. (Saturday night through next Friday) By Saturday night, a weak 500mb ridge will try to build into west Texas, which should allow for a brief reprieve from the rain.
Also went ahead and knocked down highs as temps are trending cooler. The gusty northeast winds are expected to continue today as the low pressure in Northern Illinois and Indiana moves southeast. As the low moves out of the Great Lakes Region, high pressure will be moving into Wisconsin from the northwest. The winds will also gradually diminish tonight as the high pressure moves in and the pressure gradient weakens. The cooler temperatures are expected to continue across southern Wisconsin today and tonight. Temperatures are expected to fall into the low to mid 30s overnight tonight. The end of the windy and cooler regime will come to an end on Saturday. High pressure will be in control and overhead of the state of Wisconsin.
A sharp upper level trough is spinning southeast over the Upper Midwest this afternoon, with moderate SW flow aloft. Mid-level dry air continues to advect in from the west, and a narrow zone of subsidence behind a pre-frontal trough is resulting in some very brief clearing/scattering of low clouds. Lapse rates are generally poor, but a plume of DCAPE ~800-900 J/kg is forecast to advect east across central KY immediately downstream of the cold front. Temperatures tumble overnight, and the approaching deep mid-level trough and lingering moisture should be enough for scattered light rain/drizzle. The upper trough continues to drop southeast over the Ohio Valley on Saturday.
A cold front has almost made its way through Middle Tennessee. Cold front has just about made it across Middle Tennessee, with only a few lingering showers moving through behind the boundary.
Deep convection has redeveloped along a pre-frontal trough/wind shift line from middle TN into northwest AL. The cold front in southern IL and southeast MO will arrive this evening, shifting winds to the northwest with a good dose of cold/dry advection. Overnight lows will dip into the lower 50s at most areas, and possibly upper 40s in far northwest AL if low clouds do not preclude that later tonight. The clouds and cold advection through the day will keep temperatures quite chilly, with highs only in the 60s, with upper 50s to lower 60s atop the higher Cumberland Plateau in southern TN and northeast AL.
804 PM EDT Fri May 28 2021 A broken line of showers and thunderstorms is currently stretching from roughly Carrollton to Dahlonega and moving south and east through the forecast area ahead of an advancing cold front. Better upper level forcing will continue to move into the area as the front moves in and the pre-frontal trough should provide a nice lifting mechanism for storms as can already be noted by the more vigorous convection ongoing across Alabama. Only concerns overnight appear to be the low cloud deck for aviation.
951 PM EDT Fri May 28 2021 A cold front will continue to push through the region this evening.
1003 PM EDT Fri May 28 2021 The cold front approaching the region from the west is beginning to weaken, although some isolated thunderstorms are possible as the line makes its way through SE AL and SW GA. 18 UTC surface analysis shows the cold front has moved into the Southeast and satellite imagery shows some agitated cumulus across East Central Mississippi which is likely the initial signs of storm development ahead of this boundary. The airmass out ahead of this boundary across our region is warm - but not especially moist as drier air aloft has mixed to the surface, with most areas away from the coast having dewpoints in the low to mid 60s. The cold front is expected to either move through the region or dissipate on Saturday.
The cold front albeit mixed up with outflow boundaries should drop down into SETX Saturday morning and then off the coast late Saturday afternoon/evening. Even with the upper level ridge building into the state from the west, models seem to be keeping the door open for a small chance of storms Sun afternoon given the progs of a favorable upper jet placement. 41 Light/moderate onshore winds tonight will be veering to the east (perhaps even NE for the bays) tomorrow with a weak cold frontal boundary into SE TX.
High pressure ridging into the southeastern Gulf of Mexico will shift southeast tonight through the weekend as a weak front moves into waters and washes out.
923 PM CDT Fri May 28 2021 A cold front is currently dropping south through the Mid-South, demarcated by a line of weak radar returns over north Mississippi. /issued 302 PM CDT Fri May 28 2021/ A cold front continues to move across the Mid-South this afternoon. The clouds are associated with an upper trough that will be moving through the region. A few of the CAMS are showing even some light shower activity near the KY/TN state border shortly after sunrise as the upper trof moves into the area. Otherwise, high pressure will begin build over the Ohio Valley on Saturday. The high will remain over the Ohio Valley through the holiday weekend.
Only other change was to adjust cloud cover a bit to address the high clouds moving through. Tonight, an upper level trough and attendant front will bring a line of showers and possibly isolated thunderstorms through the region. The surface pressure trough and convergence field is expected to arrive to the western border around 00Z-02Z. Behind the front on Saturday, cyclonic flow sets up aloft as the low rotates through with isolated showers and possibly a thunderstorm or two again. Temperatures on Saturday will be warmer than Friday's with lows in the 40s and highs in the mid 60s to low 70s.
/Issued 126 PM CDT Fri May 28 2021/ A cold front stretches from the Ohio Valley, across northern Arkansas and down into southeast Oklahoma this afternoon. The front will continue south as high pressure builds across the central part of the country.
The Florida Keys remain in the southwestern periphery of a large high pressure system anchored over the western Atlantic. Rain chances will remain near nil tonight and the low temperatures are expected to be in the upper 70s. From synopsis, the Florida Keys remain in the southwestern periphery of a large area of high pressure anchored over the western Atlantic.
/issued 302 PM CDT Fri May 28 2021/ A cold front continues to move across the Mid-South this afternoon. The clouds are associated with an upper trough that will be moving through the region. A few of the CAMS are showing even some light shower activity near the KY/TN state border shortly after sunrise as the upper trof moves into the area. Otherwise, high pressure will begin build over the Ohio Valley on Saturday. The high will remain over the Ohio Valley through the holiday weekend.
Although dry and less windy today, cloud cover associated with an upper trough has held temps in the 50s for much of the day but could still see a late day rise in temps with breaks in clouds and clearing moving in from the west.
Primary concern in the short term will be temperatures getting down near freezing across portions of the area tonight, mainly in a horseshoe wrapping from north of the Twin Cities through west central Wisconsin then back into south central Minnesota. Otherwise, we'll see high pressure drift east through the period with return flow leading to an increase in cloud cover and shower chances from west to east Saturday night.
548 PM CDT Fri May 28 2021 Mainly VFR conditions will be seen through this TAF period as high pressure approaches from the north after the frontal passage.
951 PM CDT Fri May 28 2021 Based on latest surface observations and satellite imagery, a cold front currently extends from northwestern Franklin County, TN to southwestern Franklin County, AL. Otherwise, gusty north-northwest flow at the surface will advect a cooler/drier airmass into the region by sunrise, but impacts from both boundary layer mixing and a postfrontal stratus deck building southward into the region should keep low temps in the l-m 50s. The clouds and cold advection through the day will keep temperatures quite chilly, with highs only in the 60s, with upper 50s to lower 60s atop the higher Cumberland Plateau in southern TN and northeast AL.
622 PM CDT Fri May 28 2021 Updated aviation section for 00z taf issuance Surface analysis shows a cold front extending from near the Wabash River into far west Kentucky.
Low temperatures are expected to be in the low 50s.
732 PM EDT Fri May 28 2021 A cold front will continue to push through the region this evening.
Flat cumulus clouds formed over the higher terrain across northern Arizona today with southwest breezes 10-20 20 MPH. Expected very similar temperatures on Saturday with slightly stronger afternoon winds as a trough of low pressure begins to develop over California.
A cool moist air mass over Western Washington will warm and dry this weekend as high pressure builds into the region.
836 PM EDT Fri May 28 2021 A cold front will move into the region tonight and into Saturday.
Barring the most recent HRRR, earlier runs were trending this direction which fit well with our mesoscale features, primarily a NW-SE axis of MLCAPEs over 3000 J/kg bisecting our CWA, a theta-E ridge and a modest southeasterly LLJ developing tonight.
The 00z raob shows a lack of moisture in the lower levels, which is expected as the frontal boundary has moved through our area and a high pressure pushes in from the west. We are encountering noticeably cooler temperatures tonight compared to previous nights, with lows ranging from the mid to high 50s in the north to mid to high 60s in the south.
We do have some surface support with the low over southwestern corner of SD with a trough extending north and south, and a stronger 998mb low over Saskatchewan. The main trough will cross tonight, with the surface boundary shifting mostly out of our area as well.
225 AM CDT Sat May 29 2021 Cold front has moved through middle TN and the upper level low will drag behind and move across the Ohio Valley today. Went on the low end of guidance.
The upper low responsible for keeping these clouds over the area will push eastward into the Ohio Valley, taking the cyclonic flow with it.
However, with an upper trough moving over western ND, it looks like there will be enough instability and mid level moisture for isolated to scattered post frontal showers to develop.
A cold front will push south through the entire forecast area bringing drier air and gusty northerly surface winds, especially during peak heating Saturday. The 00z raob shows a lack of moisture in the lower levels, which is expected as the frontal boundary has moved through our area and a high pressure pushes in from the west. We are encountering noticeably cooler temperatures tonight compared to previous nights, with lows ranging from the mid to high 50s in the north to mid to high 60s in the south.
The cloud cover has kept temperatures warmer than would be otherwise, but readings are still well-below normal with temperatures near 50 (average low is near 60).
Garuckas Chattanooga Airport, TN 70 51 76 53 85 / 0 0 0 0 0 Knoxville McGhee Tyson Airport, TN 66 51 70 50 82 / 30 10 10 0 0 Oak Ridge, TN 66 48 71 49 81 / 10 0 10 0 0 Tri Cities Airport, TN 67 50 66 47 79 / 30 20 10 0 10.
305 AM EDT Sat May 29 2021 Impactful weather: Frost/freezing conditions this morning and again tonight. High temperatures today will largely be in the low to mid 60s, falling to lows tonight in the range through the 50s with the coolest readings across NE lower.
Southeast MO and southern IL will see some of the coolest temps due to later clearing with highs just touching 60 in places, while the remainder of the area should see highs in the low-mid 60s. High pressure will continue to settle southward through the mid MS Valley tonight and this should lead to good radiational cooling in the absence of clouds.
358 AM EDT Sat May 29 2021 A cold front will settle south across central NC during the afternoon and early evening.
The upper-level low responsible for Friday's weather (currently centered over northwest Indiana) will drift southeast as it becomes absorbed into a more pronounced trough extending from Quebec. Lingering showers under this low will also diminish early this morning as cloud cover quickly clears from north to south. Though the pressure gradient will relax today as the high edges into the area from the northwest, northeast wind gusts to around 20 mph will continue into this afternoon. Though frost has been a concern early this morning upstream under the high, moderation of the airmass today will greatly reduce the local frost risk tonight.
A cold front has almost made its way through Middle Tennessee.
Temperatures should be a couple of degrees warmer than yesterday, but with mainly east flow, no big warmup is anticipated.
/Issued 804 PM EDT Fri May 28 2021/ A broken line of showers and thunderstorms is currently stretching from roughly Carrollton to Dahlonega and moving south and east through the forecast area ahead of an advancing cold front. Better upper level forcing will continue to move into the area as the front moves in and the pre-frontal trough should provide a nice lifting mechanism for storms as can already be noted by the more vigorous convection ongoing across Alabama. Only concerns overnight appear to be the low cloud deck for aviation.
We expect much of the region to get a break today as weak upper ridging builds briefly overhead. The exception will be across the higher terrain and far western areas where upslope flow will lead to more storm development this afternoon.
328 AM CDT Sat May 29 2021 A mid/upper level trof will swing south through the forecast area during the morning hours today. This trof will serve to keep stubborn cloud cover over most areas much of the day. In fact, ongoing patchy drizzle can be expected to continue ahead of the trof in many locations along/east of the MS river this morning. Once the mid level trof exits late today and this evening, skies will clear and winds will diminish.
This new low will then bring a cold front south, into the Florida peninsula overnight tonight, and possibly push it as far south as the Lake.
455 AM EDT Sat May 29 2021 A cold front will move through the region today.
/issued 923 PM CDT Fri May 28 2021/ A cold front is currently dropping south through the Mid-South, demarcated by a line of weak radar returns over north Mississippi. /issued 302 PM CDT Fri May 28 2021/ A cold front continues to move across the Mid-South this afternoon. The clouds are associated with an upper trough that will be moving through the region. A few of the CAMS are showing even some light shower activity near the KY/TN state border shortly after sunrise as the upper trof moves into the area. Otherwise, high pressure will begin build over the Ohio Valley on Saturday. The high will remain over the Ohio Valley through the holiday weekend.
305 AM CDT Sat May 29 2021 A beautiful Memorial Day extended weekend is upon us here in the Midsouth thanks to a ridge building in behind a cold front that moved across the region yesterday.
436 AM EDT Sat May 29 2021 Water vapor imagery places the Keys in between two upper-level lows/troughs, one over the central Bahamas, and the other nearing the Mississippi River Valley. High pressure centered to the northeast of Bermuda reaches southwest to near South Florida.
The pre-frontal trough has pushed tthroughthe area and will continue to slide south and east through the overnight. Some low clouds and fog is currently in place between the trough and the front, but should dissipate in coverage once front passes. Much cooler and drier air will follow behind and conditions on Saturday will be seasonably pleasant with a northwesterly breeze. Look for partly cloudy skies with lows in the 50s north to mid 60s south with highs in the lower 70s north to lower 80s south.
421 AM EDT Sat May 29 2021 A cold front will cross the area from north to south today resulting in falling temperatures.
1156 PM CDT Fri May 28 2021 Updated aviation section for 06z taf issuance Surface analysis shows a cold front extending from near the Wabash River into far west Kentucky.
Based on latest surface observations and satellite imagery, a cold front currently extends from northwestern Franklin County, TN to southwestern Franklin County, AL. Otherwise, gusty north-northwest flow at the surface will advect a cooler/drier airmass into the region by sunrise, but impacts from both boundary layer mixing and a postfrontal stratus deck building southward into the region should keep low temps in the l-m 50s. The clouds and cold advection through the day will keep temperatures quite chilly, with highs only in the 60s, with upper 50s to lower 60s atop the higher Cumberland Plateau in southern TN and northeast AL.
207 AM MDT Sat May 29 2021 Cyclonic flow aloft over the area today as an upper level low over Saskatchewan shifts eastward into Manitoba. Lower heights will bring cooler temperatures and while flow aloft has become drier still may see some orographic driven shower activity but any moisture amounts will be minimal.
An elongated low is slowly moving off to the east and an amplified upper ridge will be settling over the area behind it. Clouds and light rain will continue early this morning on the backside of the low. The distance between the trough and ridge axis will create tighter pressure gradients aloft and breezy conditions at the surface. Temperatures through the day will max out in the 60s and clear skies tonight will allow low to again drop to the low 40s.
Rain chances will start to increase significantly across north/west portions of Oklahoma (mainly after midnight) as progressive and low amplitude s/wv trough progresses across the central Rockies and influences the development of a large complex of thunderstorms over the higher terrain or Colorado and New Mexico.
Courtesy of cold air advection behind a cold front that stretches from northeastern GA to the Gadsden area of central Alabama. Further south, during the morning hours, sunshine could help high temperatures be a bit warmer (65 to 70 degrees).
130 AM EDT Sat May 29 2021 A cold front will continue to push through the region this evening.
458 AM EDT Sat May 29 2021 Surface cold front across northwest Georgia will continue to push southeastward across the area today. Lingering light rain showers are currently limited to parts of middle Georgia ahead of prefrontal trough and will continue to drift eastward through the remainder of the morning. Drier and cooler conditions will build initially into north Georgia today behind the front with breezy northwest winds and gradually clearing skies. High temperatures will run well below normal in north Georgia while Middle Georgia will still warm into the 80s ahead of the full impact of the cooler and drier airmass this afternoon.
At the surface, ridge extends from the western Great Lakes into eastern Nebraska/northeast KS. There is also good agreement between the GFS and NAM is tracking an upper impulse out of the Central Rockies and into the High Plains Sat night. Sun night into Mon morning will basically be a repeat of Sat night into Sun with another impulse moving out of the Rockies with another area of isentropic lift/moisture transport moving from the High Plains into our forecast area.
Those concerns aside, given the high impact of this late frost, I'm happy we have the headline out where it's at. WV satellite imagery depicts closed low center in southwest WI, with main piece of energy responsible for spotty shower activity on radar, pushing east across southeast IA.
322 AM CDT Sat May 29 2021 As an upper level Low pressure system pulls out of the Ohio Valley, this will bring about clearing skies throughout the day from northwest to southeast. High pressure builds into the Great Lakes region, holding northeasterly surface winds in place this weekend.
250 AM MDT Sat May 29 2021 Current surface map places weak cold front slipping into the western Dakotas as upper trof moves through the Northern Plains. Cold front slowly slides east today. Upper level ridge builds across the western CONUS this week, with dry northwest flow over the Northern Plains.
214 AM EDT Sat May 29 2021 A cold front will move into the region tonight and into Saturday.
Expect average temperatures overnight with the usual colder locations (Bellemont, Grand Canyon Village, and Window Rock) dipping down near freezing. The forecast remains on track with scattered showers and dry thunderstorms for Memorial Day as a weak area of low pressure skirts towards the south. Confidence is still on the lower side when it comes to exactly where storms will develop, but as of now best chances are for locations along the Mogollon Rim and eastward into Navajo and Apache counties. Flat cumulus clouds formed over the higher terrain across northern Arizona today with southwest breezes 10-20 20 MPH. Expected very similar temperatures on Saturday with slightly stronger afternoon winds as a trough of low pressure begins to develop over California.
In addition a longwave trough over the Canadian Prairies and Northern Plains will shift east toward the region.
A cold front will make its way through, following the rain, shifting our winds to the northwest with speeds around 10 kts with gusts around 15kts, mainly north of I-10, calming down after sunset. Temperatures for Saturday will approach 90 degrees this afternoon but will cool way down to the upper 50s for our SE AL and SW GA counties and the low 60s for the FL Panhandle.