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Itstrainingtime

Central PA Feb/March 2019 Disco: More Snow In Our Future?

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SPC AC 140601 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sun Apr 14 2019 Valid 141200Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE OHIO VALLEY SOUTHWARD INTO THE SOUTHERN APPALACHIANS... ...SUMMARY... Severe thunderstorms are forecast today in parts of the Ohio Valley southward through the southern Appalachians and northeast Gulf Coast. Severe thunderstorms are possible this evening/tonight east of the Appalachians from the Carolina Piedmont northward into parts of the Mid-Atlantic states. ...Synopsis... Maturing mid-latitude cyclone currently moving across the southern Plains is expected to become more progressive today as it moves northeastward through the middle MS Valley and into the Lower OH Valley. Strong flow aloft accompanying the system will spread eastward ahead of the upper trough, extending from the southeast through the TN Valley at midday and across the Mid-Atlantic states by this evening. Surface cyclone attendant to the upper system is expected to move quickly northeastward as well, moving through the OH valley by midday and through much of the Northeast by the end of the period. Severe threat appears to be in two somewhat discrete regimes, one associated with the ongoing storms across the Southeast within the warm conveyor and the other associated more closely with the surface low and stronger large-scale forcing for ascent accompanying the parent upper trough. ...Eastern AL...GA...SC... A line of thunderstorms will likely be ongoing at the beginning of the period across eastern AL or perhaps as far east as western GA. With the forcing for ascent (both associated with the parent upper trough and surface low) shifting northeastward, the expectation is for much of this convection to be waning, supported predominantly by a moist low-level air mass and modest convergence along the outflow. Even so, vertical shear will remain strong and few of the more persistent storms may be able to produce damaging wind gusts through the late afternoon. ...OH Valley...Central Appalachians...Northern Mid-Atlantic... Temperatures across the lower/middle OH Valley will be cool at the beginning of the period but strong warm advection is expected to result in air mass destabilization across the central OH Valley ahead of the approaching surface low. By mid-afternoon, temperatures are expected to be in the mid 60s with dewpoints in the upper 50s/low 60s. Instability will be somewhat tempered across the middle OH Valley but is still expected to be sufficient for thunderstorm development. Strong low to mid-level flow will contribute to a risk for damaging wind gusts and isolated hail. Warmer temperatures are expected with eastern extent and the general expectation is for storms to gradually strengthen as they move eastward across OH and into WV and PA. The loss of diurnal heating could lead to a short-term weakening of the storms during the early evening but this weakening will likely be compensated by a strengthening low-level jet as well as increased large-scale forcing for ascent. As a result, a modestly organized convective line appears possible as the storms move across the central Appalachians. Damaging wind gusts appear to the primary severe threat. However, a strengthening low-level jet and the resulting vertically veering wind profiles could support a few embedded tornadoes. ..Mosier/Bentley.. 04/14/2019 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z CURRENT UTC TIME: 0934Z (5:34AM), RELOAD THIS PAGE TO UPDATE THE TIME

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I just noticed  Spc is not messing around with day 4 looks to be a very bad day to have already highlighted such a huge 30% area 4 days out. Another multiple day on the way. Kinda Scary Deja vu 2011.

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ZCZC SPCSWOD48 ALL ACUS48 KWNS 140855 SPC AC 140855 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0355 AM CDT Sun Apr 14 2019 Valid 171200Z - 221200Z ...DISCUSSION... Models have come into much better agreement through the medium-range period as compared to 24 to 48 hours prior. Both now depict a strong upper trough moving out of the Rockies and into the Plains Day 4 (Wednesday 4-17), eastward into the Mississippi Valley region Day 5 (Thursday 4-18), and then across the Ohio and Tennessee Valleys Day 6(Friday 4-19). This system will be accompanied by an associated/well-developed surface low and frontal system, with the low progged to begin occluding Day 5 over the upper Midwest region. The cold front is currently expected to reach the Appalachians by the end of Day 5 (Friday morning), and then continue eastward to the coast through Saturday morning. Once the front clears the coast, surface high pressure residing over the Gulf of Mexico in the wake of the front and a weaker upper pattern suggests a relative lull in severe potential Days 7-8 (next weekend). Meanwhile however, as the system emerges into the Plains Day 4, strong -- though somewhat meridional -- flow accompanying the system should combine with an amply moist/unstable warm sector to permit storm development, within a zone of ascent focused near the low/front. Though models differ somewhat with respect to the position of the surface low, a somewhat bi-modal risk may evolve -- with one relative maximum near and ahead of the surface low where directional shear should be greatest (currently expected in the vicinity of Iowa), and a second from the southern Plains eastward into the Ozarks/Arklatex where the most substantial CAPE should evolve. Large hail and damaging winds are expected, along with some tornado risk -- especially nearer the surface low/warm front. As widespread convection develops through the overnight hours, and shifts eastward, a more complex forecast becomes apparent due to the effects of the precipitation and associated cloud cover an warm-sector destabilization for Day 5 -- and similarly for Day 6 as the expansive area of convection continues advancing eastward toward the Atlantic Coast. While details with respect to severe risk are therefore difficult to highlight this far in advance, large 15% risk areas will be maintained, given the strength of the upper system which will provide a kinematic field favorable for severe storms atop a warm/moist pre-frontal airmass. ..Goss.. 04/14/2019

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Doing an overnighter in Lancaster today into tomorrow. Better chances down that way, or up here in Tamaqua?

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The Lakes/Ohio Valley thread is a good read this morning for those of us that love snow.

There is a good picture from Macomb,IL that shows it thumping heavy snow in their town with snow on all surfaces, yes including all roads that caved.

It should put an end to the nonsense that we hear around here every year about sun angle & it being too late or early to snow & cover different surfaces. Macomb, IL is at a similar latitude to CTP, & they have only 600-700 feet elevation.

Someday, maybe we will get a mid April snow storm. That would be a lot of fun !

Here is the the picture from MaComb from the other thread this morning.

52FD2E1D-36DB-4FBC-96FD-FBEE61FB721E.jpeg

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7 hours ago, Voyager said:

Doing an overnighter in Lancaster today into tomorrow. Better chances down that way, or up here in Tamaqua?

The spc expanded the enhanced again to cover the whole state . western pa is probably under the gun the most because of timing.  Us and a chunk of OH will be the states to see the worst of it today. Storms will begin rotating in the OH valley in the next hour as the new line develops .

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1 hour ago, Flatheadsickness said:

The spc expanded the enhanced again to cover the whole state . western pa is probably under the gun the most because of timing.  Us and a chunk of OH will be the states to see the worst of it today. Storms will begin rotating in the OH valley in the next hour as the new line develops .

It looks to me like it might be a night of interrupted sleep. If I'm seeing the models right, on my small phone screen, the second line (cold front) looks to roll through around or after midnight. Am I right?

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33 minutes ago, Voyager said:

It looks to me like it might be a night of interrupted sleep. If I'm seeing the models right, on my small phone screen, the second line (cold front) looks to roll through around or after midnight. Am I right?

Yes Sir. Spc dose expect some weakening east of the Appalachians   

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By this evening, convective clusters should organize into a broader QLCS that shifts towards the Appalachians. Remnants of this plus further development are anticipated to the lee of the Appalachians from PA to VA tonight, as a secondary vorticity maximum pivots through the base of the amplified shortwave trough. Presence of mid to upper 60s surface dew points and lack of pronounced boundary-layer cooling should yield an environment supportive of bowing lines with embedded supercell structures. These will be capable of damaging wind swaths and a few tornadoes through the early morning

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4 minutes ago, canderson said:

My 4 pm flight to BWI already delayed to 7:30, landing at 11:30. I’m not flyimg home tonight I’m pretty sure. 

Hopefully things work out for you and you make it back tonight. Doesn't look like the actual squall line reaches the Susquehanna river until around 3am.

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1 hour ago, Itstrainingtime said:

Hopefully things work out for you and you make it back tonight. Doesn't look like the actual squall line reaches the Susquehanna river until around 3am.

The meso for 3” rain/hour til midnight doesn’t give me hope. 

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34 minutes ago, canderson said:

The meso for 3” rain/hour til midnight doesn’t give me hope. 

First line of warned storms will be through in the next hour or two. Then it appears there will be a break before the squall line hits after midnight. Maybe you sneak in between them?

TOR warning up the M/D line now below York county. Way too close for my comfort. 

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1 minute ago, Itstrainingtime said:

First line of warned storms will be through in the next hour or two. Then it appears there will be a break before the squall line hits after midnight. Maybe you sneak in between them?

TOR warning up the M/D line now below York county. Way too close for my comfort. 

True. As of now land at 11:25, so get to by around 1:15 am. Hope we can beat the intense rain rates.

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12 minutes ago, Itstrainingtime said:

A couple of cells in northern MD look worrisome...moving into soYork soon...then Lanco in a hour or so. Lower-level rotation will be hard to detect with radar issues (poor low coverage) here. #stayaware

Stay safe southern tier crew!

it looks like we are all under a Tornado Watch through overnight. Hopefully things die down with sunset now.

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4 minutes ago, Blizzard of 93 said:

Stay safe southern tier crew!

it looks like we are all under a Tornado Watch through overnight. Hopefully things die down with sunset now.

This is not the typical setup...these storms won't weaken with the loss of heating, unfortunately. 

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7 minutes ago, Bubbler86 said:

That line over N/W PA is pretty crazy as well.  

Warren got hit hard it appeared. 

We take off at 8, land at midnight. My drive to Harrisburg is REALLY going to suck cause we prob run head first into the second like. It’s worse than what just came through. 

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