Aikyam-Lab/Synoptic-Bench huggingface dataset:
A reinforcing shot of cooler air will largely keep high temperatures in the 60's today, while maintaining chances for showers and perhaps a thunderstorm or two through the day. To start the forecast, a large closed upper low across northern portions of SK and MB is filling in. Otherwise the most impactful point worth mentioning is a final reinforcing shot of cooler air is arriving this morning. Aforementioned upper closed low turns into an open trough and continues pushing northeastward for the last half of the week. Combine this with a developing ridge in the eastern Pacific and the Northern Rockies will reside under northwesterly flow aloft.
(Today through Wednesday) Concur with deterministic solutions that the upper pattern will remain quasi-stationary during the period, with a weak trough or weakness in the height field over the region.
The exception is the far north end of the Sacramento Valley where temperatures remain in the lower 80s.
Re-established marine layer and onshore flow has also led to cooler temperatures overnight with most place 3 to 5 degrees colder, but a few inland spots are 10 to 15 degrees and some hill locations are 25 degrees colder! Needless to say, but cloudy to start the day for coast/bays and inland valleys.
The overnight east flow is also stunting humidity recoveries (below 50% RH) across all peaks and ridges in the area. As the high pressure breaks down during the next few days, the east winds will diminish and the overnight humidity recoveries will begin to improve. Before the overnight humidities recover, the afternoon humidities in the region will hit their lowest point in this period of high pressure. The forcing mechanism is a shallow trough moving in from the west.
606 AM CDT Tue Jul 4 2023 (Today through Wednesday) Changes continue this Independence Day with a weak trough of low pressure settling across Texas in between ridges of high pressure into mid week.
524 AM MDT Tue Jul 4 2023 Broad positively-tilted upper trof extends from upper low in northern MB across MT. On the surface, low pressure is located near VTN with cold front behind it draped across northwestern NE and southern WY while high pressure pushes southward across high plains. Then convection will shift to the south as trof axis swings eastward and storms develop along frontal boundary across NE-KS- CO. Under cyclonic northwest upper flow, high pressure settles over the area for unseasonably cool temperatures, about 15 degrees below normal and lows Wed morning in the low-mid 30s in the higher elevations of the Black Hills.
Very warm if not hot and humid conditions will be seen across the area today with peak heat index readings in the low to mid 90s. After midnight showers and thunderstorms associated with the approaching cold front will begin working into the far western areas and slowly spread east toward the Mississippi by sunrise. medium confidence The cold front will move through the area during the day and early evening. Right now the model consensus has chance to likely pops on Wednesday, with the highest pops west of the Mississippi. For Wednesday night the model consensus has slight chance to likely pops with the highest pops east of the Mississippi.
High pressure will build over Arizona, bringing hot, dry, and breezy conditions through the rest of the week. Relatively stagnant pattern will continue through much of the period as the area of high-pressure gradually shifts eastward in the coming days.
Deep convection is expected to begin firing along/near the Blue Ridge during early afternoon as is typical this time of year. Therefore, other than an area of likely PoPs in Transylvania/Henderson Counties (which is more or less climatology), PoPs are mainly limited to the 20-40% range, with the lowest chances across the northwest NC Piedmont, where lower theta-E air/weak instability is expected. Overnight, expect increasing vort energy as an upper trof nears, which may keep spotty showers and perhaps a few general tstms ongoing toward daybreak. Otherwise, typical early July heat and humidity is expected with max temperatures right around climo yielding middle or upper 90s for maximum apparent temperatures in the warmer Piedmont locales.
Showers associated with an upper trough will remain to our east as it moves southeastward across the northern Rockies for continued dry weather today.
These temperatures are trending generally 5 to 10 degrees cooler than this time yesterday, valid at 115 PM PDT.
Routine summer high temperatures will be expected today as temperatures will be in the low 90s by this afternoon. /LCP/ Today and Tonight: Overall, cooler and wetter weather is expected through the period. Wl maintain a moist airmass with PWATs near two inches and surface dew points in the low to mid 70s. While high temperatures won't climb into the upper 90s as previous days, temperatures will still range from the low to mid 90s and combined with dewpoints in the 70s, heat index values around 105 degrees will be possible across these areas.
One more day of cool temperatures through tomorrow morning as our upper level trough that has brought unsettled weather conditions departs to our east. Otherwise, a dry evening is in store across the rest of the CWA as a weak upper level ridge moves in for tonight through tomorrow night.
100 PM MDT Tue Jul 4 2023 A reinforcing shot of cooler air will largely keep high temperatures in the 60's today, while maintaining chances for showers and perhaps a thunderstorm or two through the day. To start the forecast, a large closed upper low across northern portions of SK and MB is filling in. Otherwise the most impactful point worth mentioning is a final reinforcing shot of cooler air is arriving this morning. Aforementioned upper closed low turns into an open trough and continues pushing northeastward for the last half of the week. Combine this with a developing ridge in the eastern Pacific and the Northern Rockies will reside under northwesterly flow aloft.
(This evening through Wednesday) No threat for natural fireworks this evening as an elongated upper ridge holds firm over the region. The center of this ridge will draw closer on Wednesday and advect slightly warmer thicknesses our way. Otherwise, a cold front currently near I-70 in eastern CO and western KS is likely to dive south overnight before stalling near I- 40 in the TX PH tomorrow morning.
1050 AM PDT Tue Jul 4 2023 Warm afternoon highs continue, but a gradual cooling trend will continue through the remainder of this week as high pressure aloft weakens.
A cold front will move through the area on Wednesday, bringing better chances for showers and storms, including some severe storms. Wednesday will be hot and humid again, with highs near 70, then cooler weather will arrive behind the front.
Weak low level WAA hasn't been able to advance temperatures much beyond the lower 80s across the I-90 corridor while temperatures elsewhere have struggled to hit the mid 70s. SFC dew points remain elevated, in the mid to upper 60s, and some pooling in the upper 60s and lower 70s ahead of the cold front is likely.
Most of the convection appears to stay along and north of the Highway 2 corridor, but isolated convection could make it as far south as Flathead Lake. Along with the potential for scattered thunderstorms, the high resolution models are indicating that gusty outflows of 30-35 mph will accompany them as well. The highest probability (20% percent probability) for the gusty winds, will be along Highway 93 from Eureka to Flathead Lake.
Models show a mid-lvl trough moving across the northern Plains that will push a cold front into the area Wednesday. An unstable airmass ahead of the front will bring a potential for severe storms Wednesday afternoon/evening with the highest potential across the northern half to two-thirds of the area.
Deep lyr shear will remain quite weak, with this convection very outflow driven in VC of the weak trough axis overhead.
As the ridge is not solidly overhead and convective temperatures have likely been reached, we expect this activity to continue through sunset. With not much shear or steering flow to speak of, these showers/storms look to mainly just be heavy rain producers with some potential for gusty winds, especially as they collapse, given the high T/Td spread and DCAPE values well over 1000 J/kg. Overnight conditions will remain benign with temperatures only falling into the low to mid 70s. Tomorrow will be fairly similar to today except that chances for diurnal activity will be shunted a little further east as the upper level ridge slowly begins to work it's way over the area. Temperatures should stay just south of triple digits in the mid to upper 90s as the axis of the 850 mb thermal ridge remains well off to our west.
A weak upper ridge will build over the area today and allow temperatures to rise well into the 80s. Heat indices will be slightly warmer, but should stay well below advisory criteria. A weak upper level ridge will be over the area Wednesday and allow temperatures to rise above normal and possibly reach 90 degrees. A cold front will bring a chance for thunderstorms late Wednesday and Wednesday night.
238 PM MDT Tue Jul 4 2023 Satellite imagery showed a broad upper trough over the area with northerly mid level flow over the high plains. The upper trough axis was moving into the Dakotas this afternoon taking most of the upper support for ascent with it.
Activity should fizzle out tonight as daytime heating is lost and high pressure attempts to build at the surface. Tonight will be mild, with low temperatures in the mid to upper 60s in the lowlands and upper 50s to low 60s along the mountains. High temperatures are expected to climb into the upper 80s in the lowlands and 70s to mid 80s along the mountains. Rather warm dewpoints should also help to drive apparent temperatures into the 90s across most of the lowlands Wednesday afternoon.
Lift associated with the trough and weak convergence with the associated attendant front will be enough to keep likely PoPS tomorrow.
1228 PM CDT Tue Jul 4 2023 (Today through Wednesday) Concur with deterministic solutions that the upper pattern will remain quasi-stationary during the period, with a weak trough or weakness in the height field over the region.
* A cold front will push through the area today into tonight resulting in high temperatures in the 70s beginning on Wednesday.
(This evening through Wednesday) High pressure will be over the southeast US through Wednesday with low level flow out of the south and southwest. Winds in the low and mid levels will be fairly weak, so storms will not be moving very quickly. Because of this and the high PW values, heavy rainfall rates are expected in each storm, as well as high accumulation rates in any storms that move over the same areas. Overnight lows will be in the lower 70s, near normal, and highs on Wednesday will be in the upper and 80s to lower 90s with heat indices in the upper 90s.
Happy 4th of July! Conditions will remain dry for the rest of the day as the result of a weak upper level ridge. With dewpoints in the low 70s, this will make for a hot and uncomfortably humid day. Heat indices will be between 90 to 95 degrees, so make sure to take plenty of breaks in the shade if outdoors and stay hydrated! Heat and humidity during the day on Wednesday will fuel convection in the afternoon and evening as a cold front approaches from the upper Midwest.
Models still insist negative H5 height anomalies will develop across California and the Great Basin under the formation of a weak trough. The strong ridge will have shifted back over Texas and northern Mexico.
1206 PM CDT Tue Jul 4 2023 (Today through Wednesday) Changes continue this Independence Day with a weak trough of low pressure settling across Texas in between ridges of high pressure into mid week.
Current trends suggests that the coverage of thunderstorms will increase during the afternoon hours, with the highest confidence that storms will impact the terminals between 20Z and 00Z. /73 (Now through Wednesday) The forecast area remains nestled between a trough extending from the Ohio Valley, southwestward towards the Lower Mississippi Valley and a ridge over the northern Gulf of Mexico. A stronger trough is expected to dig into the Plains on Wednesday, with the ridge over the northern Gulf weakening and retreating to the south. Expect temps to be near to slightly above normal with overnight lows in the mid 70s and daytime highs in the lower 90s.
Redevelopment of strong to severe storms over the area ahead of a cold front Wednesday afternoon and evening.
An approaching cold front will become a focus for showers and thunderstorms this afternoon. Deeply mixed inverted-v profiles across our central KS counties will support a damaging wind threat with the developing line of storms along the advancing cold front. Much cooler air will overspread the area in the wake of the front with portions of central KS seeing highs in the 70s. Cooler air will overspread the area in the wake of the frontal boundary with highs in the lower 80s for most areas. Clouds and precipitation should result in another seasonably cool day with highs in the low 80s on Fri. A line of strong to severe convection is expected to develop along a southward moving cold front late this evening and overnight. This is where the highest confidence exists to maintain mention of TSRA with visibility restrictions and gusty winds.
1154 AM MDT Tue Jul 4 2023 The upper level trough continues to extend out of Canada to the west of the CWA as a cold front has made its way through northwest to southeast. Behind the front cooler temperatures below average for this time of year with sufficient enough CAA bringing with it low clouds and off an on light rain and/or drizzle throughout the afternoon and evening hours for most east of the Divide. West of the Divide should remain mainly dry with no thunderstorm activity expected at this time with the cooler, more stable air behind the aforementioned cold front. Wednesday will see a mainly stable day cooler than average for afternoon high temperatures. Nothing significant to note with these being very isolated in nature associated with the filling trough as it slowly pushes through the CWA.
Broad longwave troughing circulated over the northwest to north central CONUS this afternoon, while mild low level cold air advection amid northwest surface flow was observed over western and central North Dakota. Tonight, cold high pressure will build into western North Dakota. This should clear skies from west to east, though clouds may linger in the east as the high will be centered over the western third of the state. This is where the coldest lows should be, where a few normally cooler sites in the southwest may dip into the 30s.
(This afternoon through Wednesday) The large-scale pattern is characterized by a low amplitude upper trough over the Pacific Northwest with ridging locating across northern Baja and the Desert Southwest. Winds aloft were westerly around these features, with the flow turning more northerly through the lower troposphere. Given the pattern expect a rather slow erosion of the lower clouds today, with a gradual clearing towards the coast through the late morning and early afternoon.
A cold front will push southward into Kansas in response to a northern stream upper level disturbance. Given the high dewpoint depressions, these storms will rapidly form into a line. Given that the upper level ridge will be flattened and located to the south over New Mexico and west Texas, there will be numerous opportunities for evening and nighttime thunderstorm clusters to initiate on the favored topographic regions to the west (Palmer Divide and Raton Mesa). Given the high dewpoints, afternoons will be on the warm and "muggy" side. Elsewhere a cold front will move through southwest Kansas with a change in winds for GCK, DDC, and LBL between 04-07Z.
152 PM CDT Tue Jul 4 2023 [Key Messages] 1) Mainly dry & hot 4th of July with an isolated shower or storm 2) Increasing clouds and a better chance of showers & storms Wednesday [Discussion] A broad area of high pressure covered the Ohio River Valley into the eastern portions of the Midwest early this afternoon.
High pressure will drop over the Northern Plains later tonight through Wednesday night, with dry and cooler conditions expected. Not much overall change in the extended with dry conditions as the upper trough migrates east with weak ridging upstream and northwest flow overhead.
1033 AM MDT Tue Jul 4 2023 Broad positively-tilted upper trof extends from upper low in northern MB across MT. On the surface, low pressure is located near VTN with cold front behind it draped across northwestern NE and southern WY while high pressure pushes southward across high plains. Then convection will shift to the south as trof axis swings eastward and storms develop along frontal boundary across NE-KS- CO. Under cyclonic northwest upper flow, high pressure settles over the area for unseasonably cool temperatures, about 15 degrees below normal and lows Wed morning in the low-mid 30s in the higher elevations of the Black Hills.
124 PM EDT Tue Jul 4 2023 High pressure will keep our area mostly dry with seasonably warm temperatures.
Much cooler weather for the remainder of the work week. The focus will shift from heat to potential thunderstorms late this evening into Wednesday morning as a cold front pushes southeastward into portions of Nebraska and Iowa. Most convection will be in a low-intensity state by sunrise Wednesday, with the synoptic surface cold front entering NW MO (the convective outflow boundary with northerly winds will likely we south of the CWA by sunrise). A break in the heat will certainly be noted, with highs much cooler behind the front in the upper 70s. A few areas, if sufficient clearing can occur, may warm into the lower 90s over central Missouri.
The main concern in the short term will be the potential of thunderstorms from a cold front tomorrow evening. A large upper level trough will deepen as it moves into the upper mid west and will swing an associated cold front through Michigan tomorrow.
A few spots may see upper 50s to low 60s, but those temperatures will be reserved for the higher terrain. Tomorrow will be similar to today with highs during the afternoon a couple to a few degrees warmer. Lows tomorrow night end up being similar to or a couple degrees warmer than tonight's.
1234 PM CDT Tue Jul 4 2023 (Today and tonight) An upper level ridge currently located over eastern Arizona will slide eastward into New Mexico today.
With a weak upper trough over the region tonight, an isolated shower or storm cannot be ruled out through the night mainly over southern portions of the region. Cannot find much support in the 12Z and later guidance for the NBM's Wednesday morning PoPs over west Kentucky, but left them alone with the trough still in that area.
High pressure and heat will be the weather story for the entire period. By this weekend, much of the lowlands will likely need a heat advisory with an excessive heat watch/warning not out of the question for El Paso.
1214 PM CDT Tue Jul 4 2023 (Today through Wednesday afternoon) High pressure to our west begins exerting its influence today as it nudges east towards eastern New Mexico and West Texas. The warming trend continues tomorrow as highs edge up another degree or two with the upper ridge continuing to gradually build east.
Any showers that do form this afternoon dissipate quickly this evening as high pressure settles in overhead. The best chances will be in the higher terrain on the SE CWA border, and also in the southern coalfields.
numerous showers and thunderstorms are likely through midnight as a weather system moves through the base of an approaching upper trough. as the base of the upper trough axis moves through, we'll be waiting for the next weather system to move through from Colorado during the late afternoon through overnight hours, mainly impacting those south of a line from Yuma to Hill City. High temperatures will be cooler behind the front and under considerable cloudiness with lower 60s to middle 70s currently forecast.
Surface analysis indicates the leading edge of a cold front stretching from northwest Minnesota down through the northern plains into the Black Hills. With the approaching cold front supporting lift, the probability for isolated showers and thunderstorms will increase over the next several hours along this frontal boundary. Temperatures will be much cooler tomorrow with highs primarily in the upper 60s to low 70s.
Flat upper level ridging will nudge into the Desert Southwest. At the same time, troughing will intensify across the central-northern Great Plains. Meanwhile, solid low level southerly flow will transport deep moisture into the lower levels. Looking at the day-by-day, a cold front will slide into KS during the day Wednesday. Additional storms, some of which could be strong, may develop overnight as the cold front moves through the area.
Ongoing showers and thunderstorms associated with a mid-level trough axis continue across eastern North Texas.
A ridge of high pressure will build over the region for the middle of the week, allowing the temperatures to rise above normal during the middle of the week.
The main cold front will shift east through the area Wednesday afternoon and evening, with a round of showers and thunderstorms anticipated.
Upper ridging over the area keeps shower and thunderstorm activity mostly in check through Wednesday, with the exception being the higher terrain to the east where a few showers or storms could develop with help from the weak upslope flow.
135 PM MDT Tue Jul 4 2023 Deep upper trough over central NOAM continues to move ESE, while bringing much cooler conds to the region the next couple days. Semi-blocked flow will support a slow exit of this feature as the western NOAM long wave ridge continues its slow migration east.
Atlantic seabreeze returns at SGJ, SSI, and CRG by 16Z with VCTS at JAX/CRG and VCSH at SSI/SGJ as strong heating and seabreeze combine to create more storm coverage compared to today due to approaching cold front and increasing moisture from the Gulf of Mexico.
A few outflow- driven showers remain in the vicinity of the Lower Keys. Also, given it is July with the aforementioned sampled environment, will play it cautious and retain the low- end chance level rain chances inherited. However, mariners should be mindful of the clearance below the lowest fixed bridges along the island chain during morning high tides for the next couple of days, which are running a foot above mean higher high water (normal high tide). From synopsis, a fractured Atlantic ridge axis will reach west across Florida overnight, maintaining light to gentle breezes across the Florida Keys coastal waters.
358 PM MDT Tue Jul 4 2023 The upper level trough continues to extend out of Canada to the west of the CWA as a cold front has made its way through northwest to southeast. Behind the front cooler temperatures below average for this time of year with sufficient enough CAA bringing with it low clouds and off an on light rain and/or drizzle throughout the afternoon and evening hours for most east of the Divide. West of the Divide should remain mainly dry with no thunderstorm activity expected at this time with the cooler, more stable air behind the aforementioned cold front. Wednesday will see a mainly stable day cooler than average for afternoon high temperatures. Nothing significant to note with these being very isolated in nature associated with the filling trough as it slowly pushes through the CWA.
839 PM EDT Tue Jul 4 2023 A ridge of high pressure will build over the region for the middle of the week, allowing the temperatures to rise above normal.
Focus now turns to convection along a cold front currently across northern sections of Kansas. Flat upper level ridging will nudge into the Desert Southwest. At the same time, troughing will intensify across the central-northern Great Plains. Meanwhile, solid low level southerly flow will transport deep moisture into the lower levels. Looking at the day-by-day, a cold front will slide into KS during the day Wednesday. Additional storms, some of which could be strong, may develop overnight as the cold front moves through the area.