Aikyam-Lab/Synoptic-Bench huggingface dataset:
The center of an upper low is just off Vancouver island. At the same time an upper trough is digging south off the northwest California coast. The upper low will continue to move south off the northwest California coast during the day and the upper flow will become southeasterly. The position of the upper low is one that will bring showers just about anywhere overt the forecast area. Tonight, there's pretty good agreement that an enhanced areas of moderate to heavy precipitation will move up from the southeast into portions of the eastside, including Modoc, Lake and Klamath County late this evening and tonight as the upper low moves south.
627 AM EDT Mon May 1 2023 Gusty winds will continue through Tuesday as a strong trough dominates the weather over the Eastern CONUS. A drier and cooler air mass will be in place through mid to late week as the upper pattern is slow to change. A strong upper trough is now firmly in place over the east coast as an Omega Block pattern becomes established over the CONUS. A cooler day is expected despite abundant sunshine with forecast highs in the upper 60s to lower 70s. Anomalously deep cut off upper low centered over the Great Lakes and Ohio Valley moves slowly east and continues to dominate the eastern CONUS. Pressure ridge from the Midwest slides southeast toward the lower Mississippi Valley.
524 AM EDT Mon May 1 2023 A cold front over central PA will jump to the coast overnight, as a deep low forms off the northeast coast early Monday.
622 AM CDT Mon May 1 2023 (Today and tonight) A weak cold front will move south of the I-10 corridor before washing out this morning. No rainfall today and tonight with upper ridging suppressing storm development.
409 AM CDT Mon May 1 2023 Key Messages: * Freezing temperatures this morning and again Tuesday morning.
642 AM CDT Mon May 1 2023 (Today through Tuesday) Mid-level ridge continues to build over the state of Texas for the short term period. Today will consist of mostly clear skies with southeast winds gusting to 30 mph through the afternoon with highs reaching the low to mid 90s. Tonight will be partly cloudy as dewpoints continue to increase overnight and lows will be a bit warmer in the upper 60s.
A weather system approaching from the west will bring cooler temperatures to the region. Low pressure centered just off the Pacific NW coast will dig south today, bringing a 30% chance of showers and thunderstorms to western Humboldt county this afternoon which will increase to around 50% this evening. Temperatures will be trending cooler today and Tuesday as the low tracks south and slightly east.
A BEAUTIFUL start to May is ongoing across the Florida Keys this morning with lower humidity (dew points near 60 degrees) and slightly cooler temperatures. The Keys remain in between a ridge over the Atlantic centered near the Lesser Antilles and Puerto Rico with a strong nearly vertically stacked low pressure system over the Great Lakes region. This is leaving in the dry northwest flow behind the cold front that passed through yesterday.
604 AM CDT Mon May 1 2023 (Today and tonight) The forecast area is under northwest mid to upper level flow this morning between an omega block ridge over the Rocky Mountain states and a deep low over the Great Lakes. The ridge will move slowly eastward through tonight with some upstream cirrus spilling over the ridge overnight with some increasing cloud cover over the forecast area. Cooler air behind the front will see temperatures peak in the 70s to near 80 this afternoon.
513 AM PDT Mon May 1 2023 Low pressure near the West Coast will strengthen the onshore flow across southern California bringing much cooler weather to inland areas today with stronger and gusty west winds in the mountains and deserts into tonight.
533 AM EDT Mon May 1 2023 Low pressure tracks north of the area today then meanders over the Great Lakes before slowing moving over the northeast through the middle of the week. An upper level low then lingers over the area through the end of the week. High pressure begins to build in over the weekend. The low will continue to track nwd this mrng. Some remaining fog across ern areas will scour out as winds increase out of the W behind the low.
634 AM CDT Mon May 1 2023 KEY MESSAGES: - Warmer and drier for the week ahead.
513 AM EDT Mon May 1 2023 Low pressure tracks north of the area today then meanders over the Great Lakes before slowing moving over the northeast through the middle of the week. An upper level low then lingers over the area through the end of the week. High pressure begins to build in over the weekend. The low will continue to track nwd this mrng. Some remaining fog across ern areas will scour out as winds increase out of the W behind the low.
507 AM CDT Mon May 1 2023 (Today) Quiet/unseasonably cool wx conditions are expected across the mid TN Valley starting the new work week, as a large area of high pressure out of the northern Plains gradually begins to build towards the SSE.
An upper low will slide southward today with continued clouds and a few showers at times for the area.
One of these will move through the upper Ohio Valley this evening, along with a small tightening of the low level pressure gradient below. Synoptically, an omega blocking pattern is gradually building across the CONUS with eastern Kentucky on the eastern periphery under the downslope of the exiting trough.
730 AM EDT Mon May 1 2023 Low pressure tracks north of the area today then meanders over the Great Lakes before slowing moving over the northeast through the middle of the week. An upper level low then lingers over the area through the end of the week. High pressure begins to build in over the weekend. The low will continue to track nwd this mrng. Some remaining fog across ern areas will scour out as winds increase out of the W behind the low.
559 AM CDT Mon May 1 2023 (Today through Tuesday) Center of a broad upper level trough is currently near the Great Lakes with the trough encompassing almost 2/3's of the country which is basically from the Rockies and eastward. The center of the upper low will track northeastward today.
1038 AM EDT Mon May 1 2023 Gusty winds will continue through Tuesday as a strong trough dominates the weather over the Eastern CONUS. A drier and cooler air mass will be in place through mid to late week as the upper pattern is slow to change. A strong upper trough is now firmly in place over the east coast as an Omega Block pattern becomes established over the CONUS. A cooler day is expected despite abundant sunshine with forecast highs in the upper 60s to lower 70s. Anomalously deep cut off upper low centered over the Great Lakes and Ohio Valley moves slowly east and continues to dominate the eastern CONUS. Pressure ridge from the Midwest slides southeast toward the lower Mississippi Valley.
Our dew points are much cooler in the upper 30 and a range of 40s, so there is still plenty of room left to fall toward daybreak, and some of these clouds may clear by then as well. Could be some virga in NE LA, but too dry in the lower atmosphere to measure anywhere. Otherwise, tomorrow afternoon will see more May sunshine and highs in the lower 80s. /24/ (Tuesday Night through Monday) Dry conditions expected through midweek with strong northerly flow prevailing aloft as an upper-ridge builds across the region from the west. At the surface, high pressure extending from Canada through the Midwest into the ArkLaTex to maintain light winds and mild conditions.
Weak high pressure over the area, though a fairly tight pressure gradient remaining.
Expect few if any clouds this entire short term period, despite north to northwesterly flow at 500mb as 2 large lows rotate around the Lower Great Lakes and along the west coast. A ridge will remain squished between the 2 lows, stretching from MT to CO and TX. At the surface a ridge of high pressure set up from central canada through the western Dakotas through OK will continue to shift east across our region as it builds. The region will be situated between a large upper level trough over the eastern half of the country and ridging over the Rockies Tuesday night.
645 AM EDT Mon May 1 2023 (Today and tonight) The tri-state region is under the influence of a large upper-level troughing pattern that will continue to hold. High temperatures for today will range from the upper 70s north of I-10 to the low 80s south of I-10. Lows tonight will be in the low 50s north of I-10, mid 50s to the south, and upper 50s along the coast.
744 AM EDT Mon May 1 2023 Aviation - Unsettled Through Tuesday - A stacked cold core low will continue to rotate overhead through Tuesday resulting in generally cooler temps and wet conditions. But again, given the above freezing air temps and even warmer ground temperatures, we do not anticipate major impacts.
938 AM CDT Mon May 1 2023 High pressure in control at the surface and dry, Northwesterly flow aloft yielding plenty of sunshine and very pleasant temperatures on this first day of May.
823 AM CDT Mon May 1 2023 Temperatures have climbed above freezing this morning and the freeze warning for today has been cancelled. Sub-freezing temperatures are expected to return to a majority of the local area tonight, and a Freeze Warning remains in effect from 1 AM through 9 AM CDT Tuesday. Key Messages: * Freezing temperatures this morning and again Tuesday morning.
Should be a comfortable afternoon with temperatures climbing into the lower to mid 80s while dew points remain in the mid 50s inland to lower 60s near the coast. An upper-level trough situated to the north and centered over the Great Lakes Region continues to influence weather conditions across the FL peninsula. That should largely continue for today with mostly sunny skies and highs in the low-to-mid 80s. As the low continues to slowly lift away and ridging builds in from the Gulf, the FL peninsula begins to make the transition from more of a continental airmass back to a more tropical one - at least at the surface. While no dramatic wind shift is expected for the next couple days, a longer fetch of westerly flow over the Gulf brings more moisture back and warmer temperatures.
A short wave trough begins to push through the area during the day on Tuesday. Forecast soundings for the Permian Basin and SE New Mexico show an inverted V(denoting drier air in the low levels) with strong enough lapse rates(changes in temperature with height) to support the potential for strong, gusty winds, small to near severe(1 inch) hail, and lightning in any stronger storms that do form. Given this, rain amounts will be limited as these storms fill in the lower level dry air with moisture before rain gets to reach the ground. Storm motion will be generally west to east with activity forming over the higher terrain, like the Guadalupe, Delaware, and Davis mountains, during the early afternoon and pushing to the east across the Trans Pecos and Permian Basin into the late afternoon.
Temperatures are in the lower 50s inland to upper 50s and lower 60s near the coast. A closed, upper level low continues to spin over the northeastern portion of the country. At the surface, while a surface front meanders offshore over the northern Gulf of Mexico, high pressure will build into the ArkLaTex region and dominate through early week. Another cool night is in store tonight, as temperatures likely drop into the upper 40s to lower 50s north of I- 10 and into the lower to mid 50s south of I-10. This has necessitated extending the High Risk of Rip Currents through this afternoon for the western Florida Panhandle coast.
(Rest of today through Tuesday) Dry and benign weather will persist through early week over the southern Florida peninsula with the lack of any significant surface features and the establishment of the Omega Block synoptic upper level pattern across the CONUS (ridging over the central US while troughing flanks the ridge along the Pacific West Coast and across the Northeast).
913 AM MDT Mon May 1 2023 MORNING UPDATE: With actual highs trending warmer than what's been forecast in the NBM, decided to go ahead and raise afternoon maximum temperatures a couple degrees. -Bernhart PREVIOUS DISCUSSION: Synoptic Setup: Forecast begins with a highly amplified cool trough dropping into the eastern two thirds of Canada and the CONUS with a warm ridge building in response over the western third of both. Farther west another trough has closed itself off over the Pacific Northwest coast and is dropping south in further response. Northeast Montana lies in northern to northwestern flow aloft nestled up against the ridge to the west with some cooler air dropping in and still affecting the far east.
323 PM CDT Mon May 1 2023 An amplified mid/upper flow regime was in place across the CONUS with a deep trough over the Great Lakes area and an amplified ridge over the Rockies with another trough over the Pacific Northwest/west coast. north/northwest mid/upper flow will help steer a ridge of high pressure at the sfc over the Northern Plains southward across the area tonight. As this ridge builds in, dry air, clear conditions and light winds will allow for a period of radiational cooling. Low-lying areas may approach freezing with some scattered frost possible. Afternoon highs are expected to top out in the lower 70s.
313 PM EDT Mon May 1 2023 Weakening low pressure will continue to spin over the Great Lakes through the Short Term. Lows Tuesday morning should mostly be in the lower 40s, but sheltered rural locations will dip into the upper 30s. Those west winds will continue tomorrow but not quite a gusty as the past couple of days as the low to our north deamplifies.
1230 PM CDT Mon May 1 2023 (Today through Tuesday) Mid-level ridge continues to build over the state of Texas for the short term period. Today will consist of mostly clear skies with southeast winds gusting to 30 mph through the afternoon with highs reaching the low to mid 90s. Tonight will be partly cloudy as dewpoints continue to increase overnight and lows will be a bit warmer in the upper 60s.
The higher elevations will see some late-season accumulating snow. The overcast conditions are making a significant difference in 24 hour temperature trends: as of 1 PM PDT, Redding was running 20 deg F cooler than this same time yesterday and Sacramento International 21 deg F cooler. Longwave trough just west of the coast will setup residence for the week as an associated upper low will drop toward California overnight and into tomorrow.
1218 PM CDT Mon May 1 2023 (Today through Tuesday) Center of a broad upper level trough is currently near the Great Lakes with the trough encompassing almost 2/3's of the country which is basically from the Rockies and eastward. The center of the upper low will track northeastward today.
This will glacially spin off to east, allowing ridging to gradually build in. Temperatures, and probably even sun angle, have really affected accumulations here, but at least 1-6 additional inches are possible in the higher terrain with a trace elsewhere along the South Shore. Snow should wind down tomorrow, though this area will stay on the cooler side, closer to that cut- off low. Further into the week, we really start to see some (relative to the last two weeks) warmer temperatures with ridging and high pressure.
1219 PM MDT Mon May 1 2023 Synoptic Overview: An omega block -- characterized by an upper level trough/low along the Pacific Coast, an upper level ridge over the Rockies and High Plains, and an expansive upper trough/low over the eastern CONUS (east of the MS River Valley) -- will prevail through the short term period. Today-Tonight: Synoptic subsidence on the eastern periphery of the aforementioned ridge / western periphery of the east CONUS trough. along the western periphery of a persistent low-level (surface to 850 mb) ridge extending NNW from the Lower MS River Valley/Gulf Coast to the Dakotas. with afternoon highs in the lower-mid 70s and overnight lows in the mid-upper 40s.
306 PM EDT Mon May 1 2023 A strong upper level low pressure system over the eastern Great Lakes will continue to influence our weather through midweek. Several pieces of energy will pivot around the low bringing gusty winds, below normal temperatures, and mountain snow.
where ambient temperatures run a few degrees cooler than surroundings) across far northern Oklahoma towards daybreak Tuesday. As the eastern CONUS closed low begins to sluggishly progress eastward, the main synoptic influence looks to become an upper ridge centered across the Great Divide.
135 PM PDT Mon May 1 2023 Low pressure near the West Coast will strengthen the onshore flow across southern California, bringing much cooler weather to inland areas with stronger and gusty west winds in the mountains and deserts into tonight.
(Tonight through Tuesday night) Upper level ridge along the Rio Grande into the southern Rockies will move eastward to an axis from the southern high plains down to deep south Texas Tuesday and Tuesday night. The low level flow will be weaker for Tuesday night but low clouds will remain over the region.
(Rest of Today) A mid/upper-level cyclone centered across Lower MI this morning will shift slowly northeastward into adjacent portions of southern Ontario today, maintaining strong (75-80 knot) west-northwest flow aloft across the TN Valley.
Western and central North Dakota remains situated in between a highly amplified upper ridge to our west (axis centered over central Montana), and a stacked upper low well off to our east (centered over Lake Eerie). At the surface, expansive high pressure over the northern Plains will keep conditions dry with only some fair weather cumulus this afternoon across our eastern zones, mainly just the James River Valley. The upper ridge tries to nudge a bit closer on Tuesday as it deamplifies slightly. Ridging continues to approach and deamplify through midweek, keeping the region in a dry blocking pattern.
Upper flow will back to the southwest on Tuesday as a ridge axis moves over the area. Low level convergence in the afternoon will be maximized in eastern New Mexico along a surface pressure trough. Nonetheless, this will still garner a modest low level theta-e ridge extending northward ahead of the surface pressure trough.
A gorgeous day is ongoing across the Florida Keys this afternoon! Yesterday's late season cold front brought comfortable dewpoints our way, along with cooler temperatures. Observation sites along the island chain have temperatures in the lower 80s. An expansive mid-upper level trough currently parked over the Great Lakes region will dawdle around that area for the next few days. This feature will block subtropical ridging from nosing into our area and will act to keep this abnormally dry air we have now from exiting the region. This massive low will slowly shift eastward through the week, and the subtropical ridge will gradually set up in the Gulf of Mexico. Once the ridge has established itself, some increased moisture will ride around the northern periphery and be brought back down to the Florida Peninsula this weekend.
1253 PM CDT Mon May 1 2023 (Today and tonight) A weak cold front will move south of the I-10 corridor before washing out this morning. No rainfall today and tonight with upper ridging suppressing storm development.
The upper low offshore will slowly slide southward along the Oregon coast today, allowing for more south to southeasterly into this afternoon. An upper low will slide southward today along the coast with continued clouds and a few showers at times for the area.
231 PM MDT Mon May 1 2023 Synoptic Overview: An omega block -- characterized by an upper level trough/low along the Pacific Coast, an upper level ridge over the Rockies and High Plains, and an expansive upper trough/low over the eastern CONUS (east of the MS River Valley) -- will prevail through the short term period. Today-Tonight: Synoptic subsidence on the eastern periphery of the aforementioned ridge / western periphery of the east CONUS trough. along the western periphery of a persistent low-level (surface to 850 mb) ridge extending NNW from the Lower MS River Valley/Gulf Coast to the Dakotas. with afternoon highs in the lower-mid 70s and overnight lows in the mid-upper 40s. Trough entrenched along the west coast will be slow to lift out due to a blocky upper pattern.
CAMs still indicate scattered thunderstorms developing around 22Z mainly for parts of the high country including South Park. The upper level ridge axis will shift a little further eastward into western Colorado today. Most of the plains should be able to reach the lower to mid 70s, with 60s foothills and high valleys, and 50s mountains. The plains appear to stable once again to support any convection moving out of the higher terrain. Early in the period, Colorado will be under an upper ridge over the western states, between an upper low centered over the Great Lakes and another centered just off the coast of California. Together these features form an omega blocking pattern over North America.
253 PM CDT Mon May 1 2023 Key Points: - Very high fire danger this afternoon area-wide - Chilly Tuesday morning especially in north central KS - Increasing chances for showers and thunderstorms latter half of this week 19Z water vapor imagery depicts an upper low encompassing the eastern half of the CONUS, still centered over lower MI. Another upper trough is off the Pacific coast with an amplified ridge over the Rockies, which leaves the area solidly in a northwest flow regime. That said, if dew points were to increase slightly or temperatures trend slightly cooler, then Republic and Washington Counties could see frost/freeze conditions, so trends will need to be watched this evening for any deviations from the forecast.
1214 PM CDT Mon May 1 2023 (Today through Tuesday afternoon) This evenings cold front continues to press south, but is running out of steam given the difuse pressure gradient pattern in place across W TX. Upper level pattern out west will transition from ridging to a deep cut off upper low along the Pacific coast which will play more of a role in our weather for Tuesday through mid-week. Scattered showers/storms will initiate over the high terrain of the Davis Mtns, as well off the eastern Sacs and high plains in SE NM. Highs on Tuesday will be a few degrees warmer compared to today, much closer to seasonal norms with temps in the 80s.
1215 PM CDT Mon May 1 2023 (Today through Tuesday) Upper air analysis this morning shows northwesterly flow over Texas between a trough over the eastern half of the country and a ridge over the west. The low level flow will be from the south to southeast bringing moist air back to the region.
Pleasant weather is expected to continue through the short-term period as a ridge builds overhead the Central CONUS between a deep upper-level low over the Great Lakes region and another upper-level low diving southward along the West Coast. The weak cold front that pushed through the area over the past 24 hours has settled across South Central Texas as of this morning.
Temperatures will be mild tonight, with overnight lows ranging from the 50s across the Big Country, to the lower 60s over the southern counties. Temperatures on Tuesday will be close to normal for this time of year, with afternoon highs in the low to mid 80s.
243 PM EDT Mon May 1 2023 A large area of low pressure will bring unseasonably cold high temperatures, scattered to widespread rain showers, and breezy conditions to our forecast area through Tuesday.
358 PM EDT Mon May 1 2023 Large low pressure located over the Great Lakes region will remain over the area through Tuesday.
146 PM EDT Mon May 1 2023 A cold front just northwest of the area will move into southeast GA this afternoon and into northeast FL by late this evening. Winds will begin to settle down after sunset, with low temperatures falling into the lower 50s in SE GA and lower 60s in NE FL.