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1900hurricane

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About 1900hurricane

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  • Four Letter Airport Code For Weather Obs (Such as KDCA)
    KCLL
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  • Location:
    College Station, TX

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  1. Slow start for the WPac this year, although that has been fairly typical these past few years.
  2. Having an MCV in the bands of a Tropical Storm is just plain silly.
  3. A cell may be trying to establish itself WSW of Ardmore.
  4. Considering EML strength, Thursday, Friday, and Saturday are all at risk of a cap bust. I think the day most likely to convect is Saturday since it will probably have the strongest impulse in the 500 mb flow and the best low level moisture due to days of (possibly undisturbed) return flow. Wind fields don't look amazing, but could be sufficient in the presence of big time CAPE. Both the GFS (below) and ECMWF have been consistent in showing a scattered/widely spaced QPF signal by 00Z Sunday.
  5. I'd say there are pretty good chances that the storm SW of Abeline will end up dropping something.
  6. Approaching Medicine Lodge. Sent from my iPhone using Tapatalk
  7. The cell that tried firing near Snyder, TX looks like it's dying out.
  8. I think we're still 1.5-2 hours away from anything firing in Texas. The cumulus field still looks fairly suppressed to me. Also, the 12Z NCAR Ensembles start displaying echoes around 18Z.
  9. The new SPC Day 1 is a very good read. SPC AC 181243 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Thu May 18 2017 Valid 181300Z - 191200Z ...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS FROM PARTS OF CENTRAL AND SOUTHERN KANSAS TO NORTHWESTERN OKLAHOMA... ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS SURROUNDING THE HIGH RISK FROM WESTERN OKLAHOMA TO CENTRAL KANSAS... ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SURROUNDING THE MODERATE RISK FROM PARTS OF NORTHWEST TEXAS TO PARTS OF SOUTHEASTERN COLORADO...NORTHERN KANSAS AND EXTREME WESTERN MISSOURI... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SURROUNDING THE ENHANCED RISK AND EXTENDING INTO EASTERN COLORADO...WESTERN MISSOURI...EXTREME SOUTHERN NEBRASKA...AND THE TEXAS RIO GRANDE VALLEY NEAR DEL RIO... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEASTERN INDIANA TO WESTERN NEW ENGLAND... ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SURROUNDING BOTH SLIGHT RISKS AND BETWEEN THEM OVER THE MID MISSISSIPPI VALLEY... ...SUMMARY... An outbreak of severe thunderstorms with tornadoes, very large hail and wind damage is expected to develop across parts of the southern and central Plains from this afternoon into this evening and overnight. Some strong, long-lived tornadoes are expected, along with hail to near 4 inches in diameter, over parts of Kansas and Oklahoma. Large hail, tornadoes and wind damage also will be possible outside of these areas across parts of the southern and central Plains. Damaging gusts and sporadic hail also are expected across parts of the lower Great Lakes region to western New England this afternoon and early evening. --- Technical Discussion --- ...Synopsis... In mid/upper levels, broadly cyclonic flow will cover much of the western and central U.S., anchored by a major cyclone now centered over UT. The 500-mb low is expected to dig southeastward across the Four Corners through the period, reaching northwestern NM by the end of the period. As this occurs, the leading lobe of an 85-100-kt 250-mb jet will spread over the southern High Plains and western/ central KS through tonight. A leading shortwave trough -- currently apparent on moisture-channel imagery over WI, western Lake Superior and the MN Arrowhead -- will weaken and eject east-northeastward across southern QC to northern ME by 12Z. At the surface, 11Z analysis showed a cold front from southern QC to a low over the MI/WI border, southwestward across IL, becoming quasistationary over MO and the KS/OK border region, to a weak low over southeastern CO. The low is expected to move erratically eastward along the KS frontal segment (becoming a slowly northward- moving warm front) through the period. Today, the richer low-level moisture now over north TX and southern/central OK will advect northwestward over the outlook area. The dryline will sharpen this afternoon from northern Coahuila northward across west-central TX to southwestern KS. The cold front will move southeastward across the Great Lakes region, reaching parts of NY, New England and the Ohio Valley region overnight. ...Central/southern Plains... Scattered thunderstorms, including multiple supercells with significant-tornado, giant-hail and damaging-wind potential, still appear probable this afternoon anywhere over the moderate- and high-risk areas, and possible farther south where coverage should be more widely scattered to isolated. The progged ingredient/parameter space is ideal for a multi-hazard severe-weather outbreak from the warm-frontal zone southward for 250-300 nm ahead of the dryline: * Moderate to strong moisture and instability: moist advection of a rich Gulf air mass with 60s to near 70 deg F surface dew points, diurnally heated along/ahead of the dryline to remove CINH, beneath roughly 8 deg C/km midlevel lapse rates, yielding 3000-4500 J/kg MLCAPE. CAPE will diminish northward through the warm-frontal zone but the cut-off of surface-based inflow should be gradual, not abrupt. * Favorable lift along the dryline and in the "bent-back" zone of deep forcing closer to the surface and upper lows, * Favorable low-level and deep-layer shear, especially near the warm front and low, but also southward across the moist sector. Low-level vorticity and hodograph size each will be maximized along and somewhat north of the warm front, with 300-400 J/kg effective SRH and 50-65 kt effective-shear magnitudes common. Any discrete/sustained supercells in this environment will be capable of cyclic, significant-tornado production as well as giant, destructive hail. A note of caution on this forecast: Some uncertainties still exist, however, precluding any greater probabilities at this time -- mainly involving density and timing of convection. Initiation of too many cells in early/middle afternoon (before warm-sector hodographs and CAPE each are biggest), and/or too close to each other at once, is possible in some parts of the current moderate/high risks. This scenario, which some guidance suggests, would lend a greater wind threat and somewhat suppressed hail/significant-tornado risk with eastward extent, due to messier storm modes amidst strengthening deep-layer flow. Evidence for such a quick transition still is inconsistent in the bulk of numerical guidance, and of course observationally. While not compelling enough to modify the high or moderate risk-driving probabilities yet, this is a possibility to be monitored for potential adjustments to the outlook during the day. Regardless of timing, storm mergers and ultimate upscale growth of convective clusters appear likely, with embedded supercells, bows, and mesobeta- or smaller-scale damaging-wind swaths. Therefore, wind probabilities have been offset eastward somewhat, relative to the others. ...Northeast to mid Mississippi Valley... Widely scattered to scattered thunderstorms are expected to develop along and ahead of the front this afternoon as diabatic surface heating and low-level convergence zones (including the baroclinic zone) act against already weak MLCINH. Well-mixed subcloud layers beneath 1000-1500 J/kg MLCAPE, and the presence of 30-40 kt effective-shear magnitudes will support enough multicellular organization, and perhaps transient supercell structures, for a hail/wind threat. Nearly unidirectional prefrontal wind profiles are forecast, and some bowing clusters could develop that would enhance the wind-damage potential on smaller scales, especially over parts of NY or western New England, however, it is too soon to be specific enough with mesoscale details for a greater categorical corridor within the existing, somewhat eastward-expanded lines. The severe wind/hail threat will be more isolated, marginal and transient this afternoon and early evening southwestward toward the middle Mississippi Valley where warm-sector surface winds and frontal convergence each should be weaker. ..Edwards/Dial.. 05/18/2017
  10. I'm still in the Texas Panhandle this morning, but I'll be headed to near the OK/KS border in an hour or two. Thinking Coldwater, Medicine Lodge, or Alva at the moment.
  11. Warm front is lifting north on schedule this morning.
  12. Day 2 for Friday is out. SPC AC 180533 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1233 AM CDT Thu May 18 2017 Valid 191200Z - 201200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM WESTERN NORTH TEXAS INTO SOUTHEAST KS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TX INTO KS...EASTWARD TO THE MID-MS VALLEY... ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN AND CENTRAL PLAINS TO THE LOWER OH VALLEY...EASTWARD TO THE VA/NC COAST... ...SUMMARY... Severe thunderstorms are expected across the central and southern Plains into the middle Mississippi Valley Friday and Friday night. The most intense storms are expected from parts of north Texas through central Oklahoma and into southeast Kansas. Very large hail, damaging winds and a few tornadoes are all possible with these storms. Additional isolated strong storms are possible across parts of the lower Ohio Valley to the middle Atlantic coast. Hail and gusty winds could accompany any storms that develop in that region. ...Synopsis... The upper low/trough centered over the central/southern Rockies will eject northeast across the central and southern Plains on Friday. This will bring a band of strong southwesterly flow aloft across northern TX into the mid-MS Valley. Strong low-level south/southeasterly winds ahead of a surface low and dryline will maintain transport of rich boundary-layer moisture across the southern/central Plains vicinity. As the southern Plains surface low shifts northeast through the night, a warm front draped west to east from near the KS/NE state line into the mid-MS Valley will advance slowly northward through the period into southern IA, northern IL and central IN. Meanwhile, a surface dryline will surge eastward across OK and KS. These boundaries will be the focus for severe thunderstorm development through the period. Further east, A cold front located from southern OH into southern New England will track southward through the period. Thunderstorms, some potentially strong, may develop along/ahead of this boundary from the OH Valley into southeast VA/northeast NC in a moist and unstable environment. ...Southern/Central Plains to the Mid-MS Valley... A complicated scenario is unfolding across the region for Friday. A convective complex likely will be ongoing across parts of KS into MO/IL. This convection likely will be elevated but could still pose a hail threat given steep lapse rates and plenty of elevated instability. Additional morning convection is also possible across parts of TX into OK, though guidance varies on the extent and location of convection across this area. What guidance does agree on is that a very moist and unstable environment with very steep midlevel lapse rates and strong deep-layer shear will remain over the southern Plains. The position of the surface low will determine where the dryline and warm front are located and morning convection will impact where greatest destabilization in the vicinity of these boundaries occurs. At this time, it appears the most favorable boundary-layer conditions will exist from near the Red River vicinity of southwest OK/western North Texas into central OK along/ahead of the dryline. Discrete supercells capable of very large hail, damaging winds and perhaps a few tornadoes will be possible with these storms. The environment further to the north into southeast KS will be similar, though uncertainty is higher here given expected overnight convection on Thursday into Friday morning. Additional storms are expected to develop in the vicinity of the warm from north-central KS into northern MO. Capping concerns in this area, combined with likelihood of storms being elevated as they quickly move north of the front leads to greater uncertainty. However, very steep lapse rates and strong shear profiles will continue to support severe storms capable of very large hail. Heading into the overnight, one or more bowing complexes are expected to develop and track eastward across northern TX, OK, KS and MO. Further south into central TX, forcing will be weaker and convection will be more isolated. Still, the environment will support supercells, mainly capable of large hail, strong winds and perhaps a tornado. ...Lower Ohio Valley into Southeast VA/Northeast NC... Thunderstorms may develop in a moist and unstable environment ahead of a southward-sagging cold front. Upper forcing for ascent will be weak, as will deep-layer shear profiles. However, given steep lapse rates and moderate instability, brief, but strong storms are possible. Hail will be the main concern with these storms. ..Leitman.. 05/18/2017
  13. Also, here are reflectivities of the individual members of the aforementioned runs of the NCAR Ensembles and SSEO valid 21Z tomorrow. There are a few solutions that would mitigate things, but most look alright. Not a slam dunk either way though, although as I've stated, it appears to me more likely that the earlier storms won't be overly impinging on the main warm sector.
  14. There is a strong signal for convective initiation between 18-21Z across central Texas, and this will definitely need to be watched, but I think it's fairly likely that it won't impact the main portion of the warm sector (which I'm defining roughly as the latest SPC Day 2 Enhanced Risk area) too much. Based largely on the SSEO and NCAR Ensemble >40 dBZ neighborhood probabilities, the earlier storms appear most likely to fire in the Concho Valley, in SJT's forecast area. When running a NAM HYSPLIT trajectory matrix for the main warm sector at elevations of 100, 500, and 1000 m AGL from 18Z to 00Z, parcels appear to originate north and east of the area of most likely early convection. Now, a few of the members do initiate convection well north and east into the heart of FWD forecast area, and that convection would have an impact on at least a chunk of the main warm sector. However, based on what I see so far, this is a less likely scenario in my opinion. 00Z May 17 NCAR Ensemble >40 dBZ neighborhood reflectivity probabilities at tau 45, valid 21Z May 18. 12Z May 17 SPC SSEO Ensemble >40 dBZ neighborhood reflectivity probabilities at tau 33, valid 21Z May 18. 18Z NAM HYSPLIT backward trajectories from tau 24 to tau 30, ending 00Z May 19 for 100, 500, and 1000 m AGL, respectively.
  15. I'm taking the day off today; Iowa is just too far away for me. Already thinking about Thursday though. Not sure if I should target north or south yet (slightly leaning north at the moment), but I still have ~24 hours to decide that. In the meantime, I'm going to relax some, check out Palo Duro Canyon, and track this afternoon's storms remotely.