SPC MD 1689

5 years 11 months ago
MD 1689 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF SOUTHERN MT INTO NORTHERN WY
Mesoscale Discussion 1689 NWS Storm Prediction Center Norman OK 0144 PM CDT Sat Aug 10 2019 Areas affected...portions of southern MT into northern WY Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 101844Z - 102015Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms are expected to develop over the higher terrain of southern MT and northern WY in the next couple of hours. These storms will pose a threat for large hail and locally damaging gusts. DISCUSSION...Strong heating across southern MT into WY is resulting in a rapidly destabilizing airmass early this afternoon, especially in the I-90 corridor from LVM to BIL to GCC. CU have been increasing along the higher terrain of the Beartooth-Absaroka ranges as well as along the Big Horns. Some weak inhibition remains across the region per 18z mesoanalysis, and is likely suppressing the full potential of a storm near the southern end of the Big Horns over Johnson County WY. Most recently, this storm has produced hail a half an inch in diameter. Remaining inhibition should quickly erode over the next couple of hours with additional heating and as forcing for ascent increases modestly. Midlevel lapse rates are a bit more modest across this area than points further west where mid/upper level temperatures are cooler, but still favorable for large hail potential in the presence of 35+ kt effective shear. Thunderstorms should first develop along higher terrain and track east/northeast across the High Plains into early evening. Discrete cells or storm clusters with rotating updrafts will be capable of severe hail. Additionally, high-based storms with steep low-level lapse rates and inverted-v sub-cloud layer thermodynamic profiles will support locally damaging winds. How far northeast the threat may extend across eastern MT is somewhat uncertain. A weak cold front moved across parts of eastern MT and western ND this morning. The airmass across this area should remain capped and under the influence of at least weak subsidence, with the greater severe threat likely remaining south of I-94 across southeast MT. A severe thunderstorm watch will likely be needed for portions of the MCD area by 20z or 21z. ..Leitman/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...BYZ...RIW...TFX... LAT...LON 46521025 46740922 46640727 46260595 45780482 45180420 44570407 44060428 43810469 43680546 43660621 44120838 44380941 44671033 44871072 45671075 46521025 Read more

SPC MD 1688

5 years 11 months ago
MD 1688 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHERN CA...SOUTH-CENTRAL/SOUTHWEST OR
Mesoscale Discussion 1688 NWS Storm Prediction Center Norman OK 0136 PM CDT Sat Aug 10 2019 Areas affected...Northern CA...South-central/southwest OR Concerning...Severe potential...Watch unlikely Valid 101836Z - 102030Z Probability of Watch Issuance...20 percent SUMMARY...Isolated severe thunderstorms are possible into this afternoon, with the primary threats being locally severe wind gusts and marginally severe hail. Watch issuance is unlikely. DISCUSSION...At 1830Z, a longer-lived thunderstorm cluster is moving across far northeast CA, while other convection is beginning to develop across a larger portion of northern CA, in the vicinity of a seasonably strong mid/upper-level low. Despite widespread cloudiness and generally limited heating, cool temperatures aloft are supporting SBCAPE of 500-1250 J/kg across this region, per recent mesoanalyses. Deep-layer shear is rather limited in the immediate vicinity of the mid/upper low across north-central CA into southwest OR, but somewhat stronger within a belt of southerly midlevel flow to the east across northeast CA into south-central OR. Generally cool temperatures aloft and steep midlevel lapse rates will support some potential for marginally severe hail across the region into this afternoon. Where effective shear is stronger across the northeast CA into south-central OR, a somewhat greater risk for hail with more organized storm structures will be present, in addition to the threat for isolated severe wind gusts. In general, the severe threat is expected to remain too limited in coverage and magnitude for watch issuance. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PDT...REV...MFR...STO...PQR...EKA... LAT...LON 39992118 40062318 41352323 42662293 43542246 43812192 43902115 43732058 42962008 41301989 40932002 39992118 Read more

SPC MD 1687

5 years 11 months ago
MD 1687 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WESTERN NC AND ADJACENT PORTIONS OF UPSTATE SC AND SOUTHWEST VA
Mesoscale Discussion 1687 NWS Storm Prediction Center Norman OK 1259 PM CDT Sat Aug 10 2019 Areas affected...Western NC and adjacent portions of Upstate SC and southwest VA Concerning...Severe potential...Watch unlikely Valid 101759Z - 102000Z Probability of Watch Issuance...5 percent SUMMARY...A few strong thunderstorms are possible this afternoon, with the strongest cells capable of locally damaging wind and perhaps marginally severe hail. Watch issuance is not anticipated. DISCUSSION...Convection has been gradually increasing in coverage early this afternoon across the higher terrain of western NC and adjacent Upstate SC and southwest VA. Modest heating of a moist environment has resulted in the development of MLCAPE in the 500-1000 J/kg range, while moderate mid/upper-level flow on the periphery of a deep upper trough to the north is supporting effective shear of 30-40 kt across the region. This environment will support some potential for updraft organization, with the strongest cells capable of producing locally damaging wind and perhaps marginally severe hail. While a few marginally severe storms are possible this afternoon, the overall threat is expected to remain too marginal for watch issuance. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RAH...RNK...CAE...GSP...MRX... LAT...LON 35268277 35768242 36528153 37228102 37288024 37077963 36297963 35677976 35178025 34938065 34838096 34768167 34988274 35268277 Read more

SPC MD 1686

5 years 11 months ago
MD 1686 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF EASTERN OR...FAR SOUTHEAST WA...SOUTHWEST AND CENTRAL ID AND WESTERN MT
Mesoscale Discussion 1686 NWS Storm Prediction Center Norman OK 1241 PM CDT Sat Aug 10 2019 Areas affected...portions of eastern OR...far southeast WA...southwest and central ID and western MT Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 101741Z - 101945Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms will increase in coverage and intensity from far eastern OR into central ID and western MT over the next couple of hours. Large hail and damaging winds will be the main threats with these storms and a watch will likely be needed. DISCUSSION...Forcing for ascent is increasing across the northern Rockies late this morning, per increasing thunderstorm activity near the OR/ID border and more recently across central ID. Strong heating to the north and east of this activity is resulting in a quickly destabilizing airmass characterized by unusually high dewpoints, ranging from the low to mid 50s F mostly, but several areas are approaching 60F. As a result, MLCAPE increasing to around 1500 J/kg is expected in a swath from central ID into western MT by early afternoon. This should result in vigorous thunderstorm development over the next couple of hours over higher terrain. Effective shear greater than 35 kt will allow cells to quickly become organized with rotating updrafts and possibly some supercell structures. Midlevel lapse rates are very steep, as evident in 12z regional RAOBs. Combined with favorable vertical shear profiles, large hail will be possible. Furthermore, storms will likely be high-based as boundary layer moisture mixes out with increased heating. Steepening low level lapse rates will result and fast storm motion will aid in strong wind gust potential as well. Where higher dewpoints are maintained, forecast guidance suggests there could be a brief, conditional tornado threat, mainly over parts of western MT where east/southeasterly low level flow will enhanced effective SRH. However, this threat is more uncertain than the expected large hail and strong, locally damaging gusts. The severe threat will continue to increase over the next couple of hours as additional heating reduces inhibition and forcing for ascent continues to increase. A severe thunderstorms watch will likely be needed by 19 or 20z. ..Leitman/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TFX...PIH...MSO...BOI...OTX...PDT... LAT...LON 45411096 44971189 44531336 44011425 43211496 42591549 42261634 42171700 42421794 43091864 44141957 44701987 45251985 45931919 46631814 47021743 47471571 47751386 47711302 47411188 46831112 45861101 45411096 Read more

SPC MD 1685

5 years 11 months ago
MD 1685 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST NC...NORTHEAST SC
Mesoscale Discussion 1685 NWS Storm Prediction Center Norman OK 1237 PM CDT Sat Aug 10 2019 Areas affected...Southeast NC...Northeast SC Concerning...Severe potential...Watch unlikely Valid 101737Z - 101930Z Probability of Watch Issuance...20 percent SUMMARY...A few thunderstorms capable of locally damaging winds and perhaps some hail are possible this afternoon. Watch issuance is currently considered unlikely due to the limited areal extent of the threat. DISCUSSION...As of 1730Z, cumulus is increasing along a weak surface boundary across southeast NC, and also along the sea breeze from coastal portions of northeast SC into southeast NC. Temperatures rising into the low 90s F combined with rich low-level moisture are resulting in the development of moderate buoyancy, with MLCAPE already in the 1000-1500 J/kg range (per recent mesoanalyses) and some further increase possible this afternoon. Meanwhile, moderate mid/upper-level flow on the periphery of a deep upper trough over the Northeast is resulting in effective shear of 25-35 kt across the region. This shear will be sufficient to support some updraft organization with any deep convection that develops this afternoon. Locally damaging wind will be a threat given the potential for water-loading within a very moist environment, while any well-organized multicell or supercell structures that develop will have some hail potential, despite relatively warm temperatures aloft. The areal extent of the primary threat is expected to remain confined to near the coast, and the number of storms within the threat area remains uncertain given generally limited large-scale ascent across the region. Given these factors, watch issuance is considered unlikely, though a conditional severe threat will be present with any storms this afternoon. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM...CHS... LAT...LON 33777808 33407864 32887915 32827977 33147970 33917917 35067849 35167796 35237724 35227676 35097640 34887622 34777647 34667654 34457699 34177744 33777808 Read more

SPC Aug 10, 2019 1730 UTC Day 2 Convective Outlook

5 years 11 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NEBRASKA... ...SUMMARY... Areas of strong to severe storms are expected over portions of the northern through central High Plains Sunday afternoon into Sunday night. Large hail and severe gusts are the primary threats. ...Synopsis... Upper trough now approaching northern CA will transition to an open wave and continue through the northern Rockies and northern High Plains Sunday and Sunday night, flattening the northern periphery of an upper ridge centered over the southern Plains. A mid-level disturbance of convective origin was analyzed over far southeast AZ midday Saturday. The disturbance is forecast to move north and northeastward across western NM/CO before reaching northeast CO by early evening Sunday. Sunday morning a cold front will extend from northern MN southwest into northeast WY. The western extension of this boundary will stall before moving north as a warm front through eastern MT. A secondary front will extend from a weak surface low in IA westward through southern NE. The western extension of this boundary will stall near the KS/NE border. ...Central High Plains region... Early-day storms are forecast over KS/NE into the lower MO Valley within zone of isentropic ascent. This activity is expected to diminish as it moves east-southeastward during the day. In wake of morning storms, rich low-level moisture with mid-upper 60s F dewpoints and diabatic warming will support a corridor of moderate to strong instability (2000-2500 J/kg MLCAPE) in vicinity of the stalled front over northern KS/southern NE. Easterly upslope flow will exist north of this boundary, and storms are expected to develop over the higher terrain in association with the central Rockies impulse, as well as near the front/lee trough intersection during the late afternoon and spread east during the evening. A belt of moderate (30-35 kt) southwesterly mid-level winds will overspread the central High Plains from northeast CO into southwest NE. Some supercells are possible early over CO before outflow becomes more pervasive and storms grow upscale into clusters/lines as they develop east towards the KS/NE/CO border before spreading east overnight. Severe gusts will be the primary hazard once storms grow upscale. ...Northern Rockies through northern High Plains... Moist axis will be shunted southwestward by the south-advancing cold front, before retreating back north as a warm front through eastern MT. The corridor of modest low-level moisture with upper 50s F dewpoints beneath steep mid-level lapse rates will support moderate instability (1500-2000 J/kg from central MT through northeast WY and possibly southwest SD) as the surface layer warms during the afternoon. Storms are expected to develop over the higher terrain and spread northeast through the relatively narrow instability corridor during the afternoon and early evening. A belt of stronger winds aloft accompanying the upper trough will support 40-45 kt effective bulk shear supportive of organized storms. Large hail and severe gusts associated with high-based supercells will likely transition into outflow-efficient clusters capable of severe gusts. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 30% - Enhanced Hail: 15% - Slight ..Smith.. 08/10/2019 Read more

SPC Aug 10, 2019 1730 UTC Day 2 Convective Outlook

5 years 11 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NEBRASKA... ...SUMMARY... Areas of strong to severe storms are expected over portions of the northern through central High Plains Sunday afternoon into Sunday night. Large hail and severe gusts are the primary threats. ...Synopsis... Upper trough now approaching northern CA will transition to an open wave and continue through the northern Rockies and northern High Plains Sunday and Sunday night, flattening the northern periphery of an upper ridge centered over the southern Plains. A mid-level disturbance of convective origin was analyzed over far southeast AZ midday Saturday. The disturbance is forecast to move north and northeastward across western NM/CO before reaching northeast CO by early evening Sunday. Sunday morning a cold front will extend from northern MN southwest into northeast WY. The western extension of this boundary will stall before moving north as a warm front through eastern MT. A secondary front will extend from a weak surface low in IA westward through southern NE. The western extension of this boundary will stall near the KS/NE border. ...Central High Plains region... Early-day storms are forecast over KS/NE into the lower MO Valley within zone of isentropic ascent. This activity is expected to diminish as it moves east-southeastward during the day. In wake of morning storms, rich low-level moisture with mid-upper 60s F dewpoints and diabatic warming will support a corridor of moderate to strong instability (2000-2500 J/kg MLCAPE) in vicinity of the stalled front over northern KS/southern NE. Easterly upslope flow will exist north of this boundary, and storms are expected to develop over the higher terrain in association with the central Rockies impulse, as well as near the front/lee trough intersection during the late afternoon and spread east during the evening. A belt of moderate (30-35 kt) southwesterly mid-level winds will overspread the central High Plains from northeast CO into southwest NE. Some supercells are possible early over CO before outflow becomes more pervasive and storms grow upscale into clusters/lines as they develop east towards the KS/NE/CO border before spreading east overnight. Severe gusts will be the primary hazard once storms grow upscale. ...Northern Rockies through northern High Plains... Moist axis will be shunted southwestward by the south-advancing cold front, before retreating back north as a warm front through eastern MT. The corridor of modest low-level moisture with upper 50s F dewpoints beneath steep mid-level lapse rates will support moderate instability (1500-2000 J/kg from central MT through northeast WY and possibly southwest SD) as the surface layer warms during the afternoon. Storms are expected to develop over the higher terrain and spread northeast through the relatively narrow instability corridor during the afternoon and early evening. A belt of stronger winds aloft accompanying the upper trough will support 40-45 kt effective bulk shear supportive of organized storms. Large hail and severe gusts associated with high-based supercells will likely transition into outflow-efficient clusters capable of severe gusts. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 30% - Enhanced Hail: 15% - Slight ..Smith.. 08/10/2019 Read more

SPC Aug 10, 2019 1730 UTC Day 2 Convective Outlook

5 years 11 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NEBRASKA... ...SUMMARY... Areas of strong to severe storms are expected over portions of the northern through central High Plains Sunday afternoon into Sunday night. Large hail and severe gusts are the primary threats. ...Synopsis... Upper trough now approaching northern CA will transition to an open wave and continue through the northern Rockies and northern High Plains Sunday and Sunday night, flattening the northern periphery of an upper ridge centered over the southern Plains. A mid-level disturbance of convective origin was analyzed over far southeast AZ midday Saturday. The disturbance is forecast to move north and northeastward across western NM/CO before reaching northeast CO by early evening Sunday. Sunday morning a cold front will extend from northern MN southwest into northeast WY. The western extension of this boundary will stall before moving north as a warm front through eastern MT. A secondary front will extend from a weak surface low in IA westward through southern NE. The western extension of this boundary will stall near the KS/NE border. ...Central High Plains region... Early-day storms are forecast over KS/NE into the lower MO Valley within zone of isentropic ascent. This activity is expected to diminish as it moves east-southeastward during the day. In wake of morning storms, rich low-level moisture with mid-upper 60s F dewpoints and diabatic warming will support a corridor of moderate to strong instability (2000-2500 J/kg MLCAPE) in vicinity of the stalled front over northern KS/southern NE. Easterly upslope flow will exist north of this boundary, and storms are expected to develop over the higher terrain in association with the central Rockies impulse, as well as near the front/lee trough intersection during the late afternoon and spread east during the evening. A belt of moderate (30-35 kt) southwesterly mid-level winds will overspread the central High Plains from northeast CO into southwest NE. Some supercells are possible early over CO before outflow becomes more pervasive and storms grow upscale into clusters/lines as they develop east towards the KS/NE/CO border before spreading east overnight. Severe gusts will be the primary hazard once storms grow upscale. ...Northern Rockies through northern High Plains... Moist axis will be shunted southwestward by the south-advancing cold front, before retreating back north as a warm front through eastern MT. The corridor of modest low-level moisture with upper 50s F dewpoints beneath steep mid-level lapse rates will support moderate instability (1500-2000 J/kg from central MT through northeast WY and possibly southwest SD) as the surface layer warms during the afternoon. Storms are expected to develop over the higher terrain and spread northeast through the relatively narrow instability corridor during the afternoon and early evening. A belt of stronger winds aloft accompanying the upper trough will support 40-45 kt effective bulk shear supportive of organized storms. Large hail and severe gusts associated with high-based supercells will likely transition into outflow-efficient clusters capable of severe gusts. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 30% - Enhanced Hail: 15% - Slight ..Smith.. 08/10/2019 Read more

SPC Aug 10, 2019 1730 UTC Day 2 Convective Outlook

5 years 11 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST NEBRASKA... ...SUMMARY... Areas of strong to severe storms are expected over portions of the northern through central High Plains Sunday afternoon into Sunday night. Large hail and severe gusts are the primary threats. ...Synopsis... Upper trough now approaching northern CA will transition to an open wave and continue through the northern Rockies and northern High Plains Sunday and Sunday night, flattening the northern periphery of an upper ridge centered over the southern Plains. A mid-level disturbance of convective origin was analyzed over far southeast AZ midday Saturday. The disturbance is forecast to move north and northeastward across western NM/CO before reaching northeast CO by early evening Sunday. Sunday morning a cold front will extend from northern MN southwest into northeast WY. The western extension of this boundary will stall before moving north as a warm front through eastern MT. A secondary front will extend from a weak surface low in IA westward through southern NE. The western extension of this boundary will stall near the KS/NE border. ...Central High Plains region... Early-day storms are forecast over KS/NE into the lower MO Valley within zone of isentropic ascent. This activity is expected to diminish as it moves east-southeastward during the day. In wake of morning storms, rich low-level moisture with mid-upper 60s F dewpoints and diabatic warming will support a corridor of moderate to strong instability (2000-2500 J/kg MLCAPE) in vicinity of the stalled front over northern KS/southern NE. Easterly upslope flow will exist north of this boundary, and storms are expected to develop over the higher terrain in association with the central Rockies impulse, as well as near the front/lee trough intersection during the late afternoon and spread east during the evening. A belt of moderate (30-35 kt) southwesterly mid-level winds will overspread the central High Plains from northeast CO into southwest NE. Some supercells are possible early over CO before outflow becomes more pervasive and storms grow upscale into clusters/lines as they develop east towards the KS/NE/CO border before spreading east overnight. Severe gusts will be the primary hazard once storms grow upscale. ...Northern Rockies through northern High Plains... Moist axis will be shunted southwestward by the south-advancing cold front, before retreating back north as a warm front through eastern MT. The corridor of modest low-level moisture with upper 50s F dewpoints beneath steep mid-level lapse rates will support moderate instability (1500-2000 J/kg from central MT through northeast WY and possibly southwest SD) as the surface layer warms during the afternoon. Storms are expected to develop over the higher terrain and spread northeast through the relatively narrow instability corridor during the afternoon and early evening. A belt of stronger winds aloft accompanying the upper trough will support 40-45 kt effective bulk shear supportive of organized storms. Large hail and severe gusts associated with high-based supercells will likely transition into outflow-efficient clusters capable of severe gusts. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 30% - Enhanced Hail: 15% - Slight ..Smith.. 08/10/2019 Read more

Atlantic Tropical Weather Outlook

5 years 11 months ago

000
ABNT20 KNHC 101724
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Sat Aug 10 2019

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Tropical cyclone formation is not expected during the next 5 days.

$$
Forecaster Brown
NHC Webmaster

Eastern North Pacific Tropical Weather Outlook

5 years 11 months ago

000
ABPZ20 KNHC 101722
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sat Aug 10 2019

For the eastern North Pacific...east of 140 degrees west longitude:

A trough of low pressure located about 100 miles southwest of
Acapulco, Mexico is producing a large area of showers and
thunderstorms. Some gradual development is possible during the next
couple of days and a tropical depression could form while the system
moves west-northwestward just off the southwestern coast of Mexico.
After that time, conditions are forecast to become unfavorable for
tropical cyclone formation. Regardless of development, the
disturbance will likely bring locally heavy rainfall along portions
of the southwestern coast of Mexico during the next couple of days.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...medium...40 percent.

A broad area of low pressure located a few hundred miles
south-southwest of Manzanillo, Mexico is producing disorganized
showers and thunderstorms. Any development of this system during the
next day or so should be slow to occur due to its close proximity to
the disturbance near the coast of Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.

An area of disturbed weather is located a little less than 1000
miles south-southwest of the Baja California peninsula.
Environmental conditions are expected to become more conducive for
tropical cyclone formation by the middle next week as this
disturbance moves westward or west- northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...50 percent.

$$
Forecaster Latto/Brown
NHC Webmaster

SPC Day 1 Fire Weather Outlook

5 years 11 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 10 2019 Valid 101700Z - 111200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO FAR WEST-CENTRAL UTAH... The isolated dry thunderstorm delineation has been extended farther eastward into Idaho, where greater confidence exists for lightning atop fuels that are at least modestly receptive to fire spread. A scattered dry thunderstorm delineation was considered for parts of Oregon into Idaho, given the expected overall density of lightning. Nonetheless, wetting rains from the previous day's thunderstorm activity, combined with the expected relatively widespread coverage of heavier precipitation today, have precluded the need for a scattered dry thunderstorm area. Still, new fire ignitions are possible with strikes on the periphery of storm cores. In addition, strong to severe wind gusts may promote erratic surface conditions amidst complex terrain to potentially locally enhance fire starts or agitate ongoing fires in the absence of heavier rain, and assuming receptive fuels are present. Please see the Day 1 Convective Outlook for more details pertaining to the severe threat. Otherwise, the previous forecast remains on track. Please see below for more details. ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... A mid-level trough just off the northern California coast will begin to transition into an open wave and take on a negative tilt while ejecting toward Idaho today. As this occurs, a belt of enhanced mid-level flow will shift eastward toward the western Great Basin, overspreading dry areas of NV/UT/ID during peak heating hours. Meanwhile, areas of thunderstorms will once again affect portions of the Northwest, with isolated dry thunderstorm potential expected during the afternoon, evening, and overnight. ...Eastern Nevada, western Utah, and eastern Idaho... Beneath the belt of enhanced mid/upper flow, vertical mixing processes and a favorable surface gradient will favor increased surface winds within this corridor during peak heating hours. Areas of 15-25 mph south-southwesterly winds will become common amidst critically low RH values and broad areas of dry fuels in areas unaffected by recent rainfall. At this time, it appears that the greatest confidence of critical fire weather thresholds being exceeded will occur across east-central NV, far west-central UT, although locally critical fire weather can be expected as far north as eastern Idaho. ...Northern California through Washington and eastward into western Idaho for thunderstorms... The presence of cool temperatures aloft associated with the mid-level trough resulted in broad areas of wetting thunderstorms especially from central into north-central Oregon this afternoon and evening. These wetting downpours have undoubtedly altered fuel states in several areas, and widespread wetting thunderstorms are also expected to develop and migrate from south to north this afternoon and evening also. The isolated dry thunder area covers the potential for dry lightning strikes on the periphery of wetting thunderstorm cores in areas that continue to have cured fuels that can sustain fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

5 years 11 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 10 2019 Valid 101700Z - 111200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO FAR WEST-CENTRAL UTAH... The isolated dry thunderstorm delineation has been extended farther eastward into Idaho, where greater confidence exists for lightning atop fuels that are at least modestly receptive to fire spread. A scattered dry thunderstorm delineation was considered for parts of Oregon into Idaho, given the expected overall density of lightning. Nonetheless, wetting rains from the previous day's thunderstorm activity, combined with the expected relatively widespread coverage of heavier precipitation today, have precluded the need for a scattered dry thunderstorm area. Still, new fire ignitions are possible with strikes on the periphery of storm cores. In addition, strong to severe wind gusts may promote erratic surface conditions amidst complex terrain to potentially locally enhance fire starts or agitate ongoing fires in the absence of heavier rain, and assuming receptive fuels are present. Please see the Day 1 Convective Outlook for more details pertaining to the severe threat. Otherwise, the previous forecast remains on track. Please see below for more details. ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... A mid-level trough just off the northern California coast will begin to transition into an open wave and take on a negative tilt while ejecting toward Idaho today. As this occurs, a belt of enhanced mid-level flow will shift eastward toward the western Great Basin, overspreading dry areas of NV/UT/ID during peak heating hours. Meanwhile, areas of thunderstorms will once again affect portions of the Northwest, with isolated dry thunderstorm potential expected during the afternoon, evening, and overnight. ...Eastern Nevada, western Utah, and eastern Idaho... Beneath the belt of enhanced mid/upper flow, vertical mixing processes and a favorable surface gradient will favor increased surface winds within this corridor during peak heating hours. Areas of 15-25 mph south-southwesterly winds will become common amidst critically low RH values and broad areas of dry fuels in areas unaffected by recent rainfall. At this time, it appears that the greatest confidence of critical fire weather thresholds being exceeded will occur across east-central NV, far west-central UT, although locally critical fire weather can be expected as far north as eastern Idaho. ...Northern California through Washington and eastward into western Idaho for thunderstorms... The presence of cool temperatures aloft associated with the mid-level trough resulted in broad areas of wetting thunderstorms especially from central into north-central Oregon this afternoon and evening. These wetting downpours have undoubtedly altered fuel states in several areas, and widespread wetting thunderstorms are also expected to develop and migrate from south to north this afternoon and evening also. The isolated dry thunder area covers the potential for dry lightning strikes on the periphery of wetting thunderstorm cores in areas that continue to have cured fuels that can sustain fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

5 years 11 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 10 2019 Valid 101700Z - 111200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO FAR WEST-CENTRAL UTAH... The isolated dry thunderstorm delineation has been extended farther eastward into Idaho, where greater confidence exists for lightning atop fuels that are at least modestly receptive to fire spread. A scattered dry thunderstorm delineation was considered for parts of Oregon into Idaho, given the expected overall density of lightning. Nonetheless, wetting rains from the previous day's thunderstorm activity, combined with the expected relatively widespread coverage of heavier precipitation today, have precluded the need for a scattered dry thunderstorm area. Still, new fire ignitions are possible with strikes on the periphery of storm cores. In addition, strong to severe wind gusts may promote erratic surface conditions amidst complex terrain to potentially locally enhance fire starts or agitate ongoing fires in the absence of heavier rain, and assuming receptive fuels are present. Please see the Day 1 Convective Outlook for more details pertaining to the severe threat. Otherwise, the previous forecast remains on track. Please see below for more details. ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... A mid-level trough just off the northern California coast will begin to transition into an open wave and take on a negative tilt while ejecting toward Idaho today. As this occurs, a belt of enhanced mid-level flow will shift eastward toward the western Great Basin, overspreading dry areas of NV/UT/ID during peak heating hours. Meanwhile, areas of thunderstorms will once again affect portions of the Northwest, with isolated dry thunderstorm potential expected during the afternoon, evening, and overnight. ...Eastern Nevada, western Utah, and eastern Idaho... Beneath the belt of enhanced mid/upper flow, vertical mixing processes and a favorable surface gradient will favor increased surface winds within this corridor during peak heating hours. Areas of 15-25 mph south-southwesterly winds will become common amidst critically low RH values and broad areas of dry fuels in areas unaffected by recent rainfall. At this time, it appears that the greatest confidence of critical fire weather thresholds being exceeded will occur across east-central NV, far west-central UT, although locally critical fire weather can be expected as far north as eastern Idaho. ...Northern California through Washington and eastward into western Idaho for thunderstorms... The presence of cool temperatures aloft associated with the mid-level trough resulted in broad areas of wetting thunderstorms especially from central into north-central Oregon this afternoon and evening. These wetting downpours have undoubtedly altered fuel states in several areas, and widespread wetting thunderstorms are also expected to develop and migrate from south to north this afternoon and evening also. The isolated dry thunder area covers the potential for dry lightning strikes on the periphery of wetting thunderstorm cores in areas that continue to have cured fuels that can sustain fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

5 years 11 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 10 2019 Valid 101700Z - 111200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO FAR WEST-CENTRAL UTAH... The isolated dry thunderstorm delineation has been extended farther eastward into Idaho, where greater confidence exists for lightning atop fuels that are at least modestly receptive to fire spread. A scattered dry thunderstorm delineation was considered for parts of Oregon into Idaho, given the expected overall density of lightning. Nonetheless, wetting rains from the previous day's thunderstorm activity, combined with the expected relatively widespread coverage of heavier precipitation today, have precluded the need for a scattered dry thunderstorm area. Still, new fire ignitions are possible with strikes on the periphery of storm cores. In addition, strong to severe wind gusts may promote erratic surface conditions amidst complex terrain to potentially locally enhance fire starts or agitate ongoing fires in the absence of heavier rain, and assuming receptive fuels are present. Please see the Day 1 Convective Outlook for more details pertaining to the severe threat. Otherwise, the previous forecast remains on track. Please see below for more details. ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... A mid-level trough just off the northern California coast will begin to transition into an open wave and take on a negative tilt while ejecting toward Idaho today. As this occurs, a belt of enhanced mid-level flow will shift eastward toward the western Great Basin, overspreading dry areas of NV/UT/ID during peak heating hours. Meanwhile, areas of thunderstorms will once again affect portions of the Northwest, with isolated dry thunderstorm potential expected during the afternoon, evening, and overnight. ...Eastern Nevada, western Utah, and eastern Idaho... Beneath the belt of enhanced mid/upper flow, vertical mixing processes and a favorable surface gradient will favor increased surface winds within this corridor during peak heating hours. Areas of 15-25 mph south-southwesterly winds will become common amidst critically low RH values and broad areas of dry fuels in areas unaffected by recent rainfall. At this time, it appears that the greatest confidence of critical fire weather thresholds being exceeded will occur across east-central NV, far west-central UT, although locally critical fire weather can be expected as far north as eastern Idaho. ...Northern California through Washington and eastward into western Idaho for thunderstorms... The presence of cool temperatures aloft associated with the mid-level trough resulted in broad areas of wetting thunderstorms especially from central into north-central Oregon this afternoon and evening. These wetting downpours have undoubtedly altered fuel states in several areas, and widespread wetting thunderstorms are also expected to develop and migrate from south to north this afternoon and evening also. The isolated dry thunder area covers the potential for dry lightning strikes on the periphery of wetting thunderstorm cores in areas that continue to have cured fuels that can sustain fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

5 years 11 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Sat Aug 10 2019 Valid 101700Z - 111200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO FAR WEST-CENTRAL UTAH... The isolated dry thunderstorm delineation has been extended farther eastward into Idaho, where greater confidence exists for lightning atop fuels that are at least modestly receptive to fire spread. A scattered dry thunderstorm delineation was considered for parts of Oregon into Idaho, given the expected overall density of lightning. Nonetheless, wetting rains from the previous day's thunderstorm activity, combined with the expected relatively widespread coverage of heavier precipitation today, have precluded the need for a scattered dry thunderstorm area. Still, new fire ignitions are possible with strikes on the periphery of storm cores. In addition, strong to severe wind gusts may promote erratic surface conditions amidst complex terrain to potentially locally enhance fire starts or agitate ongoing fires in the absence of heavier rain, and assuming receptive fuels are present. Please see the Day 1 Convective Outlook for more details pertaining to the severe threat. Otherwise, the previous forecast remains on track. Please see below for more details. ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... A mid-level trough just off the northern California coast will begin to transition into an open wave and take on a negative tilt while ejecting toward Idaho today. As this occurs, a belt of enhanced mid-level flow will shift eastward toward the western Great Basin, overspreading dry areas of NV/UT/ID during peak heating hours. Meanwhile, areas of thunderstorms will once again affect portions of the Northwest, with isolated dry thunderstorm potential expected during the afternoon, evening, and overnight. ...Eastern Nevada, western Utah, and eastern Idaho... Beneath the belt of enhanced mid/upper flow, vertical mixing processes and a favorable surface gradient will favor increased surface winds within this corridor during peak heating hours. Areas of 15-25 mph south-southwesterly winds will become common amidst critically low RH values and broad areas of dry fuels in areas unaffected by recent rainfall. At this time, it appears that the greatest confidence of critical fire weather thresholds being exceeded will occur across east-central NV, far west-central UT, although locally critical fire weather can be expected as far north as eastern Idaho. ...Northern California through Washington and eastward into western Idaho for thunderstorms... The presence of cool temperatures aloft associated with the mid-level trough resulted in broad areas of wetting thunderstorms especially from central into north-central Oregon this afternoon and evening. These wetting downpours have undoubtedly altered fuel states in several areas, and widespread wetting thunderstorms are also expected to develop and migrate from south to north this afternoon and evening also. The isolated dry thunder area covers the potential for dry lightning strikes on the periphery of wetting thunderstorm cores in areas that continue to have cured fuels that can sustain fires. ...Please see www.spc.noaa.gov/fire for graphic product... Read more