Aikyam-Lab/Synoptic-Bench huggingface dataset:
A surface pre-frontal trough located along the coast this afternoon has provided moderate low level moisture convergence and is resulting in sct/num showers and a few thunderstorms. A weak cold front and associated upper trough are slowly drifting southeast with the frontal bdry currently approaching the northern CWA. Mid levels will become drier by late evening, however the low level moisture will linger, thus patchy fog will be a possibility. Winds and seas across the offshore waters may briefly reach advisory levels Sunday morning as high pressure builds across the region. The cooler airmass will be more noticeable Sun night as skies clear and winds become light, allowing for maximum radiational cooling.
Mid level ridge is still expected to slide to the west as the trough axis move through the Mid and Upper MS Valley tomorrow. As this ridge breaks down convection will become a little easier to come by especially over the northeastern half/3rd where the ridge will lose its grip first.
Showers and storms could move east from the higher terrain to the west and impact northwest Oklahoma later tonight. By late evening, higher theta-e air will be transported to the north as the low level flow increases.
Expect VFR conditions to prevail across the Rio Grande valley and northern ranchlands today as the 500mb subtropical ridge across the Gulf of Mexico and south Texas continues to provide subsidence across the area. /issued 429 AM CDT Thu Aug 17 2017/ SHORT TERM (Today through Friday): 500mb subtropical ridge across the Gulf of Mexico and south Texas will continue to provide subsidence across the CWA the next couple of days. Breezy conditions will prevail across the coastal sections this afternoon before the pressure gradient weakens across the lower TX coast Friday. Low to mid level moisture will increase across the lower TX coast Friday.
Influence from an upper high that moved in from the east overnight has dried the profile and developed a bit of a subsidence inversion in the 925 to 850 mb layer. /issued 332 AM CDT Thu Aug 17 2017/ Upper level analysis shows a somewhat weak ridge centered over the northeastern Gulf of Mexico while a trough races northeast across the upper Mississippi River Valley towards Canada. Subsidence from the high pressure aloft will limit convective coverage today compared to previous days. As the previously mentioned trough moves into Canada near the Great Lakes, a secondary trough will dip out of Canada into the Northern Plains. This feature will track on a more west to east direction, which will suppress the ridge that is currently close to the CWA.
Weak surface ridging will spread across the area tonight as the low pushes off to the northeast. The weekend is shaping up to be dry as high pressure builds in behind the departing upper trough.
Synoptic Setup: A zonal flow setup is anticipated thoruhg the short term with a succession of troughs and ridges embedded within the flow. The first ridge is located over teh Pacific Northwest adn British Columbia and is attached to the warm air over the Desert Southwest. The first trough is located just of the coast of British Columbia. Meanwhile the Ridge to the west will move across western Montana. Friday: Ridge will move across the area quickly pushing out any cool air during the morning.
534 PM EDT Thu Aug 17 2017 A warm front will push northward across the region this evening and overnight and a cold front will push across on Friday. After the cold front passes, the air will dry out and fair weather will follow for the weekend and into the new week. High pressure is now to our east and the region is in the deep southerly flow. This drier air and the leading edge of the cold front should sweep across Pennsylvania during the day and be to our east Friday evening.
544 PM EDT Thu Aug 17 2017 High pressure will crest over the area tonight. A warm front will approach Friday then lift across the area Friday night.
The dry air in the high country should bode well for the burn scar areas today, keeping the flash flood threat to a minimum.
This activity is associated with an approaching cold front draped SW to NE in this general vicinity. Overall, HI values will remain in the low 100s W/upper 90s to ~100 E.
248 PM CDT Thu Aug 17 2017 A beautiful afternoon across the Lwr Missouri Vly as high pressure remains in control for the time being. Afternoon temps have warmed into the lower 80s across most areas, with noticeably less humidity thanks to drier air following last night's frontal passage. Similar conditions should persist through the overnight hours with lows fall into into the lower 60s for most. This will ultimately result in a weak boundary lifting north across the area with scattered shwr/storm chances Friday morning, with additional activity possible during the afternoon hours as associated cold front passes later in the day. For now, best severe potential looks to hold off until after 21z as wind fields aloft should be increasing during this timeframe as main trough axis passes just to our north.
306 PM CDT Thu Aug 17 2017 19z/2pm surface analysis shows a cold front advancing slowly eastward across central Illinois, with the boundary essentially along the I-55 corridor. Once the front passes, skies will become clear and low temperatures will drop into the lower to middle 60s.
239 PM EDT Thu Aug 17 2017 Cold front tonight into Friday.
350 PM EDT Thu Aug 17 2017 High pressure will shift east tonight as a warm front approaches from the southwest. Showers and thunderstorms are possible with the warm front after midnight tonight into Friday, especially in northern New York.
especially in the low levels. Temperatures will be a few degrees cooler than today due to the NW flow.
301 PM CDT Thu Aug 17 2017 Pleasant and quiet conditions have prevailed today, with northwesterly surface winds on the backside of the closed upper low bringing drier airmass over the region. Lingering showers and isolated storms could persist through mid- morning, then partly sunny skies will give way to a warmer but seasonably day with afternoon dewpoints in the lower 60s. As the 75 knot to 85 knot upper level jet max dives south on Friday evening scattered thunderstorms will be possible along and east of the Buffalo Ridge. The freezing level also down about 4000 feet from yesterday and closer to 10000 feet AGl which would support a better chance for hail.
Updated the forecast through tonight, mainly to reflect the latest consensus of the higher resolution short term models' timing on the rain. Rain comes to an end today as the low pressure system centered over the Twin Cities early this morning lifts northeast towards eastern Lake Superior tonight. Rain showers will gradually come to an end from west to east today, with winds becoming out of the north in the wake of the low. Cooler today in the 60s for highs, then lows in the 50s tonight as skies clear out. Warmer with highs in the mid 70s to near 80 Friday.
555 PM EDT Thu Aug 17 2017 Rain is likely with a cold front tonight into Friday. The cold front currently extends from near Cincinnati toward Cleveland at this hour. Cooler air will finally arrive Friday night with the frontal passage having not occurred until Friday afternoon.
542 PM EDT Thu Aug 17 2017 Cold front tonight into Friday.
starting to see signs of monsoonal moisture return flow per 700-500mb moisture around a building upper level high over Texas.
Mid/upper level high pressure across the Gulf of Mexico extended a ridge axis across SE GA today which was suppressing deep convective growth, but daytime heating and high moisture content still sparked small but widespread showers. Before sunrise Fri, light WSW steering flow will enhance rainfall potential along this trough axis across Apalachee Bay, with convection expected to increase across the Suwanee River Valley from the Gulf during the morning hours, potentially reaching the JAX metro area by noon Fri. Additional convection will pop along the Atlantic sea breeze and across SE GA near the trough axis under daytime heating Fri, with once again high moisture and several low level forcing boundaries combining to bring a chance of a few strong storms capable of strong wind gusts as well as locally heavy rainfall mainly Fri afternoon.
209 PM EDT Thu Aug 17 2017 High pressure over the area today will bring dry weather to the area with high temperatures in the 70s to around 80. A warm front will approach the region later tonight from the southwest and enhance the potential for showers and a few thunderstorms across the area.
We will have very weak south/southwesterly flow aloft on the west side of an encroaching upper level ridge, with a relative absence in upper level energy.
1225 PM CDT Thu Aug 17 2017 Strong surface and upper level low positioned just northeast of the forecast area, near Gaylord Minnesota as of 08Z. Deep northwest flow behind the departing low will bring gusty conditions to the region today, especially in eastern areas, whereas locations west of I-29 will begin to see influence of surface ridging by mid afternoon. However, the ridging and associated subsidence behind the low should bring mostly sunny skies to most areas by mid afternoon, with temperatures climbing much closer to mid-August normals. Low level jet impinging on elevated warm front near the Missouri River Valley should focus greater rain potential in our southern counties, though broad lift ahead of the wave may lead to scattered light showers even north of I-90. On Friday, a cold front will move through the region.
With that said, it looks like the most probable situation is that convection will develop across the higher terrain of Colorado and then slowly drift towards western Kansas. As a result, have the higher pops in the western zones and lower values to the east.
The wind was the result of pressure gradient between a high pressure center along the gulf coast and low pressure over Wisconsin. A cold front trailed from the low pressure, down to the Ozark region. Drier, but not really cooler, air will build in for Friday afternoon, and will continue through the weekend.
318 PM CDT Thu Aug 17 2017 Early afternoon water vapor imagery today depicted a progressive synoptic pattern that will persist for tonight and into tomorrow with a longwave trough over the central CONUS.
Upper level ridge remains over the Pacific northwest. The upper ridge flattens out a bit with more westerly flow aloft.
403 PM EDT Thu Aug 17 2017 A cold front will move through the region late in the overnight and into the morning on Friday.
329 PM EDT Thu Aug 17 2017 Rain is likely with a cold front tonight into Friday. Cooler air will finally arrive Friday night with the frontal passage having not occurred until Friday afternoon.
Highs will range from the lower-mid 90s inland, and upper 80s along the coast.
Overall chances of storms will decrease through the weekend as ridging aloft builds over the southern plains in a pattern more typical of the time of year.
315 PM CDT Thu Aug 17 2017 18Z surface data indicates the cold front runs from eastern Wisconsin, down to KSTL, and then into northeast Oklahoma. After sunset, dry conditions will be seen along with clearing skies as high pressure moves through the area. Friday night: Significant short wave/cold front will move across the cwa, with showers and thunderstorms (some possibly strong) in the evening. This weekend: Models quickly return a zonal flow to the area, with warmer temperatures but dry conditions, as weak high pressure will be over the area.
1233 PM CDT Thu Aug 17 2017 15z/10am surface analysis shows 998mb low over western Wisconsin, with cold front trailing southward along the Mississippi River. High temperatures will top out in the lower to middle 80s. However, both the NAM and GFS indicate CAPE's east of I-57 reaching above 1000 J/kg by midday, ahead of the actual cold front, which is currently back across eastern Iowa and northern Missouri. Main upper flow will be coming out of the northwest late this week, as ridging strengthens along the western Rockies.
443 PM EDT Thu Aug 17 2017 A warm front will push northward across the region this evening and overnight and a cold front will push across on Friday. After the cold front passes, the air will dry out and fair weather will follow for the weekend and into the new week. High pressure is now to our east and the region is in the deep southerly flow. This drier air and the leading edge of the cold front should sweep across Pennsylvania during the day and be to our east Friday evening.
The clouds wrapping around a large low pressure system lifting northeast from the U. Westerly winds will remain elevated overnight, gradually relaxing from west to east later tonight as the low pulls away. An occluding low pressure system will track from northern Wisconsin towards Lake Superior tonight. We'll see a bit more sunshine on Friday as low pressure pulls away.
Given the lowered chances of any TS affecting the east coast, have dropped the VCTS and went with VCSH for now. /issued 354 AM EDT Thu Aug 17 2017/ Latest water vapor imagery shows a large dome of high pressure dominating the Florida peninsula, with little in the way of synoptic features to note. Maximum temperatures will range from the low to mid 90s across the region, a couple degrees warmer than average for this time of year.
1145 AM MDT Thu Aug 17 2017 Current satellite indicates the secondary trough pushing across NE Utah and NW Colorado. A few clouds and sprinkles with this passing trough, but quite dry below 550 mb as seen in SLC's 00z sounding. Upper level moisture associated with this trough will keep some high clouds across NE Utah and NW Colorado, and the Four Corners this morning, but skies are anticipated to clear this afternoon. High pressure will amplify over the region the next couple of days.
The cold front that was the catalyst for these storms is extending along a Unionville to MCI like as of 3AM. Conditions will be much less humid with dewpoints falling into the upper 50 and lower 60s this afternoon and highs in the low to mid 80s.
The line is ahead of a cold front. Redevelopment is likely this afternoon as the cold front pushes into the Mid-South. The clouds and convection will keep highs generally in the mid to upper 80s thus heat indices should remain below 105 degrees despite the high dewpoints.
Temperatures at BNA are already in the mid 80s with dew points in the low to mid 70s.
303 PM EDT Thu Aug 17 2017 A warm front will approach from the southwest tonight and Friday and will gradually push east of the region Friday night.
An mature storm system continues to spin over central MN early this morning, with the CWA about the see the passage of the cold front. However, models are showing a bout of lift along the cold front through sunrise, and that may allow for an increase in coverage over the Illinois counties. Low clouds wrapping around the back side of the low are expected to spread east today, and will likely be overcast for a few hours this morning in the north 1/2, then remain that way through early afternoon in the far north. This figures into the high temperatures forecast, though we will have a very mild start, weak cold advection and cloud cover will keep the north in the lower to mid 70s, while deeper mixing and sunshine to the south will have lower to mid 80s expected.
421 PM EDT Thu Aug 17 2017 High pressure will crest over the area tonight. A warm front will approach Friday then lift across the area Friday night.
556 PM EDT Thu Aug 17 2017 A warm front will approach from the southwest tonight and Friday and will gradually push east of the region Friday night.
At 230 am, the leading band of showers with the 850 warm front was lifting over northern Wisconsin early this morning. Scattered convection was noted over west central Wisconsin as the upper low continues drifts into the state from Minnesota. 00 range early this morning, there was some potential for heavy rainfall, but the 35 kts LLJ was allowing a quick storm movement, before the higher pwats shift to the east toward daybreak.
Sharp pressure gradient and trop fold with the low this morning.
438 PM EDT Thu Aug 17 2017 A rather strong storm system near the upper Great Lakes was bringing a flow of warm and humid air to the area ahead of a cold front today. The actual cold frontal passage and change in air mass is not expected until Friday, and additional showers and thunderstorms can not be ruled out ahead of the front on Friday, especially in southeast KY where the front will arrive the latest. Friday night the entire area should be dry as surface ridging builds in from the west. The drier air mass should also allow for somewhat cooler lows.
For CAPE this evening, the best numbers are over the mountains, Palmer Ridge and far eastern border. CAPE decreases on Friday according to the models, with some over the mountains, foothills and Palmer ridge. For Temperatures, Friday highs are 0- 2 C warmer than this afternoon's. The upper ridge over the South will move North into southern Colorado Friday night and into the weekend.
Perhaps of more concern will be tomorrow (Friday) where warm, dry, and gusty west winds will increase for the Northern Rockies ahead of a dry cold front that will approach by late Friday night.
322 PM EDT Thu Aug 17 2017 A warm front will push northward across the region this evening and overnight and a cold front will push across on Friday. After the cold front passes, the air will dry out and fair weather will follow for the weekend and into the new week. Warm front aloft seems to be passing overhead right now. The chance of rain and thunderstorms increases overnight as a deep cyclone moves into the western Great Lakes. Several distinct LLJ features will stream north across the CWA during this period ahead of an approaching sfc cold front. Sfc cold front hurries on through per most guidance.
Still some lingering cloud cover over the far eastern CWA on the back side of the low pressure system that brought rain to the area yesterday. Because here, winds are actually light under the ridge axis and low levels are still moist. For later today, expect the clouds across the east will have pushed off and it appears to be a mostly sunny day across much of the area with warmer temps ranging from the upper 70s to the upper 80s. A nice warm-up after the cooler readings of past days.
326 PM EDT Thu Aug 17 2017 High pressure over the area today will bring dry weather to the area with high temperatures in the 70s to around 80. A warm front will approach the region later tonight from the southwest and enhance the potential for showers and a few thunderstorms across the area.
307 PM EDT Thu Aug 17 2017 Cold front tonight into Friday.
In the east and northeast, the latest low pressure system that brought the valley and surrounding areas more rain continues to slowly shift east-northeast as the upper low over southern MN ejects NE into the upper Great Lakes. Sat looks to be more tranquil with high pressure at sfc and aloft coupled with approaching 850 mb thermal ridge.
High pressure building aloft will limit convective coverage today with the best chance for showers/storms being across the ern sites during max heating. Aloft the region is under a weakness between two ridges to the east and west, however a slightly drier air mass has moved in aloft. Today a decrease in rain chances is expected as the slightly drier air mass and ridging builds in aloft, however with ridge not firmly in control, isolated to scattered storms are still expected. The sub-tropical ridge will remain to the east of the region through the period.
312 PM CDT Thu Aug 17 2017 Tonight through Friday Latest Rap and Satellite imagery showed the region under the influence of a mid to upper level ridge center off near the northern Gulf of Mexico. Mid afternoon temperatures were in the lower 90s with some heat indices near 105 degrees. As far as temperatures are concern highs will be from the upper 80s to the lower 90s.
At the surface, high pressure resides across the Dakotas with a weak trof of low pressure extending from eastern Montana into central Wyoming. A warmer and drier airmass will move over the area for the rest of the week and most of the weekend as near zonal flow develops over the region.
A mid level trough is currently tracking northeastward over the Great Lakes region, and is responsible for the surface cold front pushing through the area this morning. Later tonight the high pressure retreats to the southeast and return flow develops over western and central KS. Also another mid level trough digs across the northern plains, which will aid the moisture return. Models are depicting convection forming along the resulting front over the high plains. Lows tonight will range from the lower to mid 60s.
A low level jet will set up with the lee side trof, increasing the low level helicity values.
102 PM CDT Thu Aug 17 2017 Surface analysis shows a high pressure system across the forecast area this morning with clouds and precipitation around during the day. Expect a weak upper level ridge to nudge across the plains on Friday.
An upper level low pressure trough at 200-300 mb extended into the forecast area from the southern Gulf of Mexico. A shear axis was in place over the western part of the upper trough, mainly across the northern and central parts of the state. Finally, an upper level high pressure ridge extended across the northern Gulf of Mexico to over the forecast area.
Highs today in the low to mid 80s will be able to drop back into the low to mid 60s for lows tonight. Friday will be drier behind the cold front with more sunshine.
An occluding low pressure system will track from northern Wisconsin towards Lake Superior tonight. We'll see a bit more sunshine on Friday as low pressure pulls away.
/issued 1010 AM EDT Thu Aug 17 2017/ Weak ridging at the surface and aloft will continue across the area through early Friday.
Upper level high pressure over the Eastern Pacific began to build east into California this afternoon. Temperatures across the area were generally between 5 and 8 degrees warmer compared to 24 hours ago and are expected to climb to seasonable normals. The high res ARW and NMM indicate an uptick in activity through the early evening hours.
157 PM EDT Thu Aug 17 2017 Weak high pressure moves off the coast today. A cold front will move into the area this weekend and stall.
Showers and thunderstorms chances will increase today ahead of a cold front which moves across the area tonight. Drier and cooler conditions are expected on Friday, as high pressure moves into the area. Ongoing storms this evening along pre-frontal trof with moderate instability over the area. Actual cold front does not move through until late tonight, so a few showers/thunderstorms could linger until the passage. Low temperatures to range from the upper 60s northwest to the lower 70s southeast. Temperatures will be cooler and closer to normal, with highs on Friday in the lower and middle 80s, Friday night will have dry weather under a ridge of high pressure.
Ridge axis is expected to become situated a little further north, which will open up a little earlier onshore flow conditions for the Space and Treasure Coast. The 00z GFS showed mid level inverted trough shifting west over the Gulf of Mexico early in the period, with ridge building in behind it over Florida.
Recently, most activity has congealed along a line from just gulf side of the Lower Keys to waters near and south of the Dry Tortugas. Forecast - Over the next couple of days, high pressure will remain across central Florida, maintaining light mostly easterly breezes. Meanwhile, an upper level low will track westwards across south Florida and the Keys. This will be accompanied by a lower level trough.
Showers and storms will redevelop later this afternoon as daytime heating creates a instability to go along with a very moist airmass and upper level trough. Abundant deep layer moisture and a broad upper level trough have resulted in an environment that has supported the development or continuation of convection this morning.