15% |
30% |
Thunderstorms |
1: Marginal |
2: Slight |
3: Enhanced |
4: Moderate |
5: High |
2% |
5% |
10% |
15% |
30% |
45% |
60% |
Sig |
5% |
15% |
30% |
45% |
60% |
Sig |
5% |
15% |
30% |
45% |
60% |
Sig |
199 ACUS01 KWNS 110051 SWODY1 SPC AC 110050 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0650 PM CST Sun Nov 10 2024 Valid 110100Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms will remain low across much of the U.S. through tonight. ...01Z Outlook Update... Boundary-layer destabilization beneath the mid-level cold core now approaching southwestern Ontario and the Lake Huron/Georgian Bay vicinity has remained quite weak, with warmer layers aloft tending to minimize lightning production in widely scattered ongoing convection. Probabilities for additional convection capable of producing lightning will become increasingly negligible as the upper impulse progresses into Ontario through 03-05Z. Otherwise, low-level moistening on southerly return flow has contributed to a corridor of weak pre-frontal boundary-layer destabilization across the lower Mississippi into lower Ohio Valleys. Beneath weak mid-level troughing now shifting east of the middle/lower Mississippi Valley, forcing for ascent may be sufficient to support some further increase in weak thunderstorm development this evening across northeastern Mississippi into portions of south central Kentucky. This will tend to advect east-northeastward into a less unstable environment as boundary-layer instability wanes to the west with the loss of daytime heating, leading to diminishing potential for thunderstorms late this evening into the overnight hours. ..Kerr.. 11/11/2024 $$
551 ACUS02 KWNS 101723 SWODY2 SPC AC 101722 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 10 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms will be possible on Monday along parts of the eastern Gulf Coast, Atlantic Seaboard and in the western states. No severe threat is expected across the continental U.S. Monday or Monday night. ...DISCUSSION... A mid-level trough will move through the eastern U.S. on Monday, as a cold front advances southeastward into the Mid-Atlantic and southern Appalachians. Ahead of the front, thunderstorms will be possible on Monday within a moist airmass across the eastern Carolinas. Isolated storms may also occur along a sea breeze boundary in coastal parts of south and east Florida. In addition, some lighting strikes may occur in the central Gulf Coast, in association with the outer bands of Tropical Cyclone Rafael. In the western U.S., thunderstorms may develop on Monday ahead of a mid-level trough from the Sierras northward into western Oregon and western Washington. No severe threat is expected across the continental U.S. Monday and Monday night. ..Broyles.. 11/10/2024 $$
504 ACUS03 KWNS 101916 SWODY3 SPC AC 101916 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0116 PM CST Sun Nov 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High Plains Tuesday evening. ...Southern High Plains... A mid-level trough will move into Rockies on Tuesday, as a broad belt of low-level flow strengthens across the Great Plains. At the surface, a cold front is forecast to advance eastward into the southern and central High Plains on Tuesday. Moisture advection ahead of the front will result in a north-to-south corridor of maximized low-level moisture across west Texas, where surface dewpoints are forecast to be in the 50s F and lower 60S F. MUCAPE is expected to increase into the 1000 to 1200 J/kg range along the moist axis by late afternoon, as mid-level lapse rates steepen due to the approach of the trough. Low-level convergence ahead of the front is forecast to become maximized early Tuesday evening, which should result in isolated to scattered thunderstorm development across the southern High Plains. NAM forecast soundings in the eastern Texas Panhandle at 03Z on Tuesday have effective shear near 40 knots, with 3-6 km lapse rates near 7 C/km. This may support isolated supercell development, with a potential for severe hail. The storms are expected to be elevated and marginal in nature, due to factors such as the late arrival of the trough, and relatively weak instability. ..Broyles.. 11/10/2024 $$
046 ACUS48 KWNS 100926 SWOD48 SPC AC 100924 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0324 AM CST Sun Nov 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Predictability concerns that are evident on D3/Tuesday appear to affect the extended period. Non-GEFS/GFS models support a slower/southward evolution of a shortwave trough across the central states into the East on D4-5/Wednesday-Thursday. The 00Z deterministic ECMWF/UKMET are quite similar with this scenario. While the surface cyclone reflection may be weak, rich Gulf moisture coupled with an increase in low-level flow may be sufficient for at least a low-probability severe threat centered on the Lower MS Valley to the northeast Gulf Coast/southern Deep South. Late week, there continues to be above-average agreement with a positive-tilt longwave trough developing from the Canadian Prairies to off the southern CA coast. Despite typical predictability concerns with the handling of embedded shortwave impulses, the primary impactful difference is with the degree of moisture return across the Great Plains. Non-GEFS/GFS models have trended towards poorer-quality return flow in the wake of the leading shortwave trough on D4-5 and subsequent continental air mass intrusion into the Gulf. As such, despite SPC and NSSL GEFS-based ML guidance depicting 5-15 percent severe probabilities next weekend, other models seemingly suggest a 5 percent or less threat for now. ..Grams.. 11/10/2024