Aikyam-Lab/Synoptic-Bench huggingface dataset:
VFR conditions as high pressure over the region will keep weather dry and benign. Model and sfc analysis data still depict high pressure dominating the Florida peninsula during the short term, although the ridge is gradually getting compressed/enlongated by a large mid level trough over the central CONUS and gradually pushing east. This will keep overall subsidence and relatively warmer air in place across SoFlo through Saturday. Also, pressure gradients will increase today between those two synoptic systems, while the ridge slowly migrates eastward into the west Atlantic. Models seem to be slowing down the progression of a sfc frontal boundary, associated with the aforementioned trough, not bringing its influence over SoFlo until after the short term.
A brief minimum in convective coverage is expected through the overnight hours tonight as the primary severe concern initially will remain to the west with an ongoing large MCS rapidly progressing eastward across the Lower Mississippi Valley. Uncertainty remains regarding eastward extent of the higher severe probabilities by Saturday afternoon, but the severe threat is expected to gradually lessen as stronger wind profiles diminish and instability lessens across eastern Georgia. Quieter conditions return just beyond the end of the short term behind the cold front which will push into the area Saturday night.
The big story today will be noticeably cooler temperatures in the upper 50s to lower 60s in most places (-5 to -15F colder than yesterday) due to a moist east/southeast flow that will lock-in low clouds east of the Allegheny Divide (US-219 corridor). Downsloping on the westside of the mtns will provide more sunshine, warmer temperatures, and possibly an isolated t'storm this afternoon near or along CTP/PBZ border. Low clouds with pockets of light rain/drizzle and patchy fog will be common over much of CPA (east of the higher terrain) tonight. The question will be how much sunshine can break through the low clouds. If low clouds win out, then it will be much cooler than fcst particularly across parts of east-central PA. Aside from the low clouds, the first part of Saturday should be rain-free.
For this afternoon: A warm front moved north into the northern CWA over the last several hours, leading to increasing dew points (SGF increased from 32F at 9pm to 40F at 3am). There is a threat for multiple rounds of heavy rainfall to the left of the low track, with hi-res models generally showing potential for 1-3" (locally higher). Saturday will be cooler with rain showers as the upper low moves through the area.
A large closed low was stacked over southwest Wisconsin with several lobes of vorticity rotating around the main circulation center as it drifted northwest. An impressive trough of warm air aloft reached from the mid Atlantic through the Great Lakes and then back down the Missouri River Valley. Another compact storm system was dropping into Wyoming and will track toward eastern KS by tonight, and a low amplitude trough with accompanying jet was worth noting over New Mexico as it will help drive severe weather in the southern CONUS later today. A slight warmup is expected for the weekend with mid level ridging building into the region.
302 AM MDT Fri Apr 9 2021 Lingering rain/snow will be found across the Big Horns region and far Dakota border counties this morning before high pressure and drier air take over to prevail for the rest of the day. Some slick locations are still possible in these areas due to overnight wet snow, especially on bridges, but otherwise additional weather impacts are expected to be minimal. We will see upper ridging and downslope flow develop today.
GOES-16 global composite water vapor imagery loop clearly showing upper low spinning over the Iowa, Minnesota and Wisconsin border early this morning as a kicker trough moves into eastern parts of Montana and Wyoming. Meanwhile, KIND-88D was showing some weak returns over west central Indiana in wraparound from the upper low. Upper low will move to the western Upper Peninsula of Michigan this evening as the trough closes into an upper low over southern Nebraska and northern Kansas. With clouds rolling in again tonight, temperatures should get no cooler than the middle 50s. Height falls above this area of CAA will lead to a broad area of low pressure through the mid to upper levels.
513 AM MDT Fri Apr 9 2021 Strong cold front is moving through central SD at this time, with very gusty winds behind it across much of the western SD plains. Further east, areas of light rain and snow will develop this morning, especially from the Pine Ridge into parts of central SD. Some light snow accumulations are possible over the Pine Ridge later this morning.
1045 AM EDT Fri Apr 9 2021 Winds out of the S/SE will continue across the area, with high pressure east of Florida. It will be another warm and dry day, with highs in the low to mid 80s along the coast and mid to upper 80s inland. (Previous Discussion) High pressure over the western Atlantic will produce a southerly wind flow.
Strong cold front is moving through central SD at this time, with very gusty winds behind it across much of the western SD plains. Further east, areas of light rain and snow will develop this morning, especially from the Pine Ridge into parts of central SD. Some light snow accumulations are possible over the Pine Ridge later this morning.
Cloudy skies with high temperatures in the low to mid 80s are expected with a few pop-up light showers.
/issued 315 AM EDT Fri Apr 9 2021/ For today and most of Saturday high pressure east of the state will bring southerly winds and increasing temperatures and moisture to the area. Having said that, once again dry air will mix down from the lower atmosphere providing low relative humidities away from the coast.
An upper low noted on 08z/3am water vapor imagery over southwest Wisconsin will continue to track N/NW today. Thanks to increasing amounts of sunshine and southwesterly winds gusting 20-30mph, high temperatures will be considerably warmer than they were yesterday. Readings will range from the lower 60s far north. Lows will mostly be in the lower to middle 50s, with cooler upper 40s far north. Widespread rain will be ongoing early Saturday morning as low pressure tracks into central Illinois. Based on the track of the low, the steadiest deformation zone rain will focus from northern Missouri into northwest Illinois by afternoon.
An elongated area of high pressure remains parked over the western Atlantic, with the associated large-scale ridging prompting scant moisture above 950 mb. With temperatures already near 80 at most island communities, did tick up the high temperatures a degree or two.
Satellite and radar showed low pressure spinning over the Upper Mississippi Valley with the band of moisture and lift that gave us yesterday's showers (and a brief spinup tornado in Cumberland County), now moving well to our north. Later today and tonight, the pattern will repeat with another low pressure system spinning across the Mississippi Valley region causing another front and series of impulses to rotate across the Lower Ms Valley, Tn Valley, and Southeast.
High pressure off the west coast will keep the area dry with above normal temperatures for the next several days.
A cold front, along with strong pressure rises, will produce gusty northwesterly winds today, especially this morning. A persistent low pressure system over Wisconsin will continue producing light showers over the far eastern CWA into the morning hours. Upper level ridging will move into the region tonight into Saturday, bringing much above normal temperatures. The main challenge in the long range will be incoming cooler temperatures and precip chances through the first half of the period. Weak high pressure remains progged by guidance to be over our forecast area as this period begins Saturday night.
Saturday will be dry and warmer with breezy to windy conditions for the afternoon into the evening. Saturday evening has the approach of the next system with moisture moving into the northwestern corner of the state with a trough.
Current temperatures are generally running a few degrees warmer compared to 24 hours ago across most of the area and range from the 30s and 40s in the mountains to the upper 40s and 50s across the Central Valley and foothills.
(Today and tonight) Early morning observations show a cold front moving down the lee of the Rockies entering NE CO. Dewpoints may climb into the low to mid 60s within the warm sector. The cold front should be near the I-44 corridor around 21Z. Further south, deeper in the warm sector, stratus (CIN) and a drier mid to upper level airmass could limit the storm coverage along the cold front until it progresses further east later this evening. Gusty north winds behind the cold front across western OK should near 45 mph this afternoon so we went ahead and issued an advisory.
Models are hinting at better coverage of storms shifting into west Alabama this evening, as forcing increases ahead of approaching short wave trof. The highest threat for damaging winds and tornadoes with the QLCS should be along and south of line from Carrollton, to Tuscaloosa, to Centreville, to Wetumpka, to Hurtsboro.
Today, as the CO shrtwv digs through the base of the trough supporting the development of another closed low over the central Plains, the WI low will be nudged northward. Despite the cloud cover, the mild airmass will support highs into the mid 50s, with cooler conditions along the Great Lakes. Tonight, with the mid level low moving north of the area, the approaching mid level ridge will help bring an end to most of the lingering light rain showers. Lows will only drop into the lower 40s. A warm front is expected to move over south and east Upper Michigan Saturday afternoon.
High pressure today will provide for warmer temperatures and dry conditions. However, a strong weather system and cold front will bring cool and windy conditions along with another round of showers Saturday into Saturday night. While this raises fire weather concerns, the surface winds will decrease compared to today as the surface pressure gradient will weaken under the transient ridge. Another Pacific low pressure trough will move through the area Saturday into Saturday night. However, this system will be somewhat different than the one today, in that it looks to introduce a broad upper level trough to much of the central United States.
Will maintain the chance for strong to severe storms for tonight ahead of a cold front, especially across central Louisiana.
624 AM CDT Fri Apr 9 2021 (Today and tonight) Early morning observations show a cold front moving down the lee of the Rockies entering NE CO. Dewpoints may climb into the low to mid 60s within the warm sector. The cold front should be near the I-44 corridor around 21Z. Further south, deeper in the warm sector, stratus (CIN) and a drier mid to upper level airmass could limit the storm coverage along the cold front until it progresses further east later this evening. Gusty north winds behind the cold front across western OK should near 45 mph this afternoon so we went ahead and issued an advisory.
An additional upper level trough was digging across the northern Rockies. As this upstream wave moves into the central plains by this evening, it will help finally to eject the downstream upper low northeast into southern Canada by Saturday morning. As the low pulls away this afternoon and this evening, showers will diminish from the south as the mid- levels dry out. RAP/NAM soundings indicate low- level clouds/moisture stuck underneath warming mid-level temps overnight so lows will likely remain in the low to mid 40s after highs in the 50s today. The rain in combination with breezy north winds thanks to a tightening pressure gradient on the western periphery of the surface cyclone will make for a raw day.
539 AM CDT Fri Apr 9 2021 As seen by current satellite, the upper level low center is presently located over the Upper Mississippi Valley very early this morning. The upper level low will slide into the northern Great Lakes region by this evening, and with mid level cooling and a less defined TROWAL, showers will become more scattered through the day - ending from west to east into this evening. It will be a cool night as lows drop into the lower to mid 30s where skies clear first, while upper 30s to lower 40s will be found elsewhere.
Look for plenty of sunshine and warm temperatures in the low-level southerly flow, with afternoon highs pushing 80. As yet another closed upper low dives into eastern Kansas after midnight and a sfc reflection develops near St Louis, precip chances will increase through the night with 50-60 POPs getting into southern Indiana and our KY counties west of I-65. On Saturday morning, a closed upper low, in the middle of a split jet stream, will sit near the Ozarks. While at the surface, a low pressure center sits near St Louis, and as these two lows join together, their trailing cold front will strengthen about the time it makes it to the western edge of Kentucky. Things look very "stable" in the low levels, but after virtual temperature CAPE values are figured, there is plenty of instability for thunderstorms to develop.
Turning cooler, windy and wet today. An upper trough translating southeast from the northern Rockies across the Central Plains today will send a cold front south through our region this morning. The upper trough deepens/closes off across Nebraska and in increasing lift, chances for rain showers return to our area this afternoon and continue into the overnight hours. With the increasing cloud cover and rain around today, have kept temperatures conservatively cool and similar to the previous forecasts with highs ranging from around 50F in our western zones to the low/mid 60s in the east. but it'll feel cooler with the windy and damp conditions. The upper low pressure system gradually tracks southeast into eastern KS/western MO Saturday late tonight/Saturday morning and the precip will taper off/end from northwest to southeast.
The southern half of Minnesota will be stuck in the deformation zone today as the upper low moves into western WI. As the low pulls away this afternoon and this evening, showers will begin to diminish from the south as the mid-levels dry out. Most ares will dry out overnight as the low finally exits into southern Ontario. Temperatures will be cooler today, with highs only in the mid 40s to lower 50s and low temperatures near 40, a far cry from the 70s/80s earlier this week. Otherwise it'll be relatively dry as ridging builds into the Northern Plains. Cloud cover should begin to dissipate from the west to the east on Saturday with highs in the lower to mid 50s.
BT Lingering rain/snow will be found across the Big Horns region and far Dakota border counties this morning before high pressure and drier air take over to prevail for the rest of the day. Some slick locations are still possible in these areas due to overnight wet snow, especially on bridges, but otherwise additional weather impacts are expected to be minimal. We will see upper ridging and downslope flow develop today.
and Saturday The main focus of the short-term portion of the forecast will focus on rain chance into the first part of the weekend along with slightly cooler temperatures. As the low lifts northward tonight, expected the chances for rain showers to slowly diminish from the south and southwest. Late in the night the next low pressure system is expected to slide across the mid-Mississippi Valley; however, not impacts are expected from that system through tonight. Otherwise, temperatures will be kept a bit cooler today, with highs mainly in the low to mid 50s. Lows are forecast to be in the low to mid 40s. Saturday: The mid-Mississippi Valley low pressure system has continued the westward trend with the latest guidance. The low is forecast to shift from near St.
931 AM EDT Fri Apr 9 2021 Dry stable conditions under high pressure covering the forecast area will again support another beautiful warm dry day across all of west central and southwest Florida with just a few afternoon clouds expected. High pressure from the western Atlantic extending west across the Florida peninsula and into the eastern Gulf will maintain pleasant boating conditions on the Gulf waters the remainder of today with southeast to south winds around 10 knots with slight seas, with an onshore sea breeze component developing along the coast during the afternoon. Despite the low humidity and high ERC values, light winds will preclude Red Flag conditions.
Pattern synopsis and forecast: Deep mid and upper level low pressure continues to slowly move north across western Wisconsin early this afternoon. With loss of warm conveyor belt and all those clouds, temperatures are several degrees cooler than the last few days (mostly in the 50s and lower 60s), but still running at least a few degrees above normal for today's date. Wisconsin low pressure will turn more northeast and begin to pick up some speed, cutting across central Lake Superior during the overnight hours. The next upper level low pressure system evident on water vapor imagery across the Montana/Wyoming region will track east southeastward over the next couple of days.
Most recent surface analysis shows a cold front moving fairly quick across far northwest Oklahoma, with a pre-frontal sfc boundary extending along and near I-44 in northeast OK to west of the OKC area, where an apparent wave was present along the boundary.
CD Chattanooga Airport, TN 80 61 72 52 72 / 30 60 90 40 10 Knoxville McGhee Tyson Airport, TN 80 58 73 53 70 / 10 30 80 50 10 Oak Ridge, TN 79 58 72 51 70 / 10 40 90 50 10 Tri Cities Airport, TN 77 55 73 54 68 / 10 20 70 50 20.
Showers and thunderstorms may still be ongoing the first thing tomorrow morning across the southern portions of the forecast area, however activity will quickly come to an end as the cold front continues to pass through the region.
257 PM MDT Fri Apr 9 2021 A strong Pacific weather system and cold front will bring cool and windy conditions along with another round of snow showers Saturday into Saturday night. The surface cold front associated with this system will advance quickly across the region from northwest to southeast through the day. The strong westerly flow will limit precipitation across lower elevations east of the Rocky Mountains, but scattered showers are likely later Saturday afternoon into evening as cold air advection steepens the mid level lapse rates, and as the low level flow develops a brief upslope component Saturday night.
Otherwise, the focus for rain will be from the Brainerd Lakes and Aitkin areas through International Falls in a deformation zone on the westward side of low pressure across the area.
Winds will shift to the northwest following the passage of a cold front this evening.
With the second round of storms, the environment will be a tad bit cooler making any severe potential supportive of all modes including, hail, strong winds, and a few tornados. High temperatures will range from the low 70s in the north to upper 70s in the south and even around 80 degrees in the Pine Belt region.
CAMs show this activity weakening before the better chances move in with the Plains trough/ahead of the cold front overnight through the morning hours.
114 PM EDT Fri Apr 9 2021 Weakening low pressure provide the chance of showers and thunderstorms this weekend. An upper low will deepen as it shifts across the midwest on Saturday.
With high pressure continued to be parked off the Eastern seaboard, near-nil rain chances are expected through tomorrow afternoon. A mid-latitude trough over the southern States will gradually push the aforementioned high eastward. This has the potential to reach at least portions of the Lower and Middle Keys. In addition, both the most recent deterministic runs of the GFS and the HRRR convective-allowing model suggest a potential line of convection ahead of the trough may develop in the Gulf of Mexico during this time and survive to also reach at least portions of the Lower and Middle Keys.
A cold front, attached to the aforementioned low pressure system, will begin moving into the Big Country this evening. Behind the front, winds will shift to the northeast, ushering in much cooler but more seasonable air. Overnight lows Friday night will range from the mid 40s in the Big Country to the low 50s down in the Hill Country. Highs Saturday will be 15 to 20 degrees cooler than today, ranging from the mid 70s to the low 80s.
Skies remain clear across the remainder of the area, and sunny skies will prevail through the evening with afternoon temperatures around 5 to 10 degrees warmer than yesterday's readings.
/issued 931 AM EDT Fri Apr 9 2021/ Dry stable conditions under high pressure covering the forecast area will again support another beautiful warm dry day across all of west central and southwest Florida with just a few afternoon clouds expected. High pressure from the western Atlantic extending west across the Florida peninsula and into the eastern Gulf will maintain pleasant boating conditions on the Gulf waters the remainder of today with southeast to south winds around 10 knots with slight seas, with an onshore sea breeze component developing along the coast during the afternoon. Despite the low humidity and high ERC values, light winds will preclude Red Flag conditions.
301 PM CDT Fri Apr 9 2021 Tonight: Cold front will continue to push southeast into shallow moisture. Wavy warm front snakes across northeast OK, with good convergence and richer surface moisture to the south. Virtually all models suggest storms/precipitation will become widespread in the vicinity of cold front and warm front late this afternoon and evening.
306 PM CDT Fri Apr 9 2021 Tonight: Cold front will continue to push southeast into shallow moisture. Wavy warm front snakes across northeast OK, with good convergence and richer surface moisture to the south. Virtually all models suggest storms/precipitation will become widespread in the vicinity of cold front and warm front late this afternoon and evening.
312 PM CDT Fri Apr 9 2021 Gusty northwest winds continue across the area this afternoon as a result of a tight pressure gradient between low pressure to the east and high pressure approaching from the west. Wind speeds will diminish this evening as the high reaches the western Dakotas, then settles in over the region overnight and Saturday. The high will begin to get pushed eastward later in the day Saturday as a frontal boundary approaches from the west.
CAMs have the next round of storms moving across the TN River around 4 or 5 am and that could be sooner if the front/upper trough rush eastward a bit quicker tonight. Low level shear and helicity will be strong enough that a tornado or two can not be ruled out, especially since the LLJ will ramp up this evening and overnight ahead of the front and upper low.
The 12Z GTF sounding reveals a significant subsidence inversion has developed at mid-levels, creating stable conditions associated with warmer temperatures and rising heights aloft. High pressure today will provide for warmer temperatures and dry conditions. However, a strong weather system and cold front will bring cool and windy conditions along with another round of showers Saturday into Saturday night. While this raises fire weather concerns, the surface winds will decrease compared to yesterday as the surface pressure gradient is not as strong under the transient ridge. Another Pacific low pressure trough will move through the area Saturday into Saturday night. However, this system will be somewhat different than the one today, in that it looks to introduce a broad upper level trough to much of the central United States.
205 PM MDT Fri Apr 9 2021 Latest upper level analysis has weak closed low just to the southeast of the Black Hills, with a sharp ridge moving into the Northern Rockies. Sharp upper ridge crosses the area Saturday. Upper ridge shifts quickly east Saturday night as a strong cold front drops through the area.