Tropical Storm Karina

Post Tropical Karina Track 2000 Hours September 16 2020
Post Tropical Karina Track 2000 Hours September 16 2020

Post Tropical Karina Wind Speed FieldTropical Storm Karina –NWS Central Pacific Hurricane Center Honolulu HI 800 PM PDT Wed Sep 16, 2020

Karina has lacked deep convection for sufficiently long to be deemed a post-tropical cyclone, and this is the last NHC advisory. Satellite imagery shows a well-developed low cloud swirl that is estimated to be producing winds to 30 kt, primarily based on an earlier ASCAT pass. Karina is moving northwestward at 8 mph, and although a turn toward the west is expected the next day or so, it will remain over 23C waters. This will prevent the redevelopment of significant convection, and the cyclone is expected to gradually spin down until it becomes a trough and dissipates in a couple days.

FORECAST POSITIONS AND MAX WINDS

INIT  17/0300Z 23.3N 125.0W   30 KT  35 MPH - Low (WSW Todos Santos, Mexico)
 12H  17/1200Z 23.7N 125.9W   30 KT  35 MPH - Low (WSW Todos Santos, Mexico)
 24H  18/0000Z 23.9N 126.9W   25 KT  30 MPH - Low (WSW San Carlos, Mexico)
 36H  18/1200Z 23.8N 128.0W   20 KT  25 MPH - Low (WSW San Carlos, Mexico)
 48H  19/0000Z 23.5N 129.3W   20 KT  25 MPH - Low (WSW San Carlos, Mexico)
 60H  19/1200Z...DISSIPATED

NWS National Hurricane Center Miami FL 800 AM PDT Wed Sep 16, 2020

Very little deep convection with cloud tops of -40C remains this morning, and what’s left is located well to the west-northwest of the center of circulation. There could still be a few 35-kt winds remaining in that particular area, which was identified earlier by a scatterometer pass, so the initial intensity is held at a generous 35 kt for this advisory. Karina is expected to continue traversing cooler waters while moving farther into an inhibiting thermodynamic environment and unfavorable upper-level winds. Therefore, weakening is forecast and Karina should degenerate to a remnant low tonight.

The initial motion is estimated to be northwestward, or 310/7 kt. A turn back toward the west-northwest is expected later today and the cyclone should continue on this general motion through Thursday night. A westward turn is forecast on Friday as Karina degenerates to a remnant low and is steered by the low-level tradewind flow.

FORECAST POSITIONS AND MAX WINDS

INIT  16/1500Z 22.6N 123.9W   35 KT  40 MPH - Tropical Storm (WSW Todos Santos, Mexico)
 12H  17/0000Z 23.2N 125.0W   30 KT  35 MPH - Low (WSW Todos Santos, Mexico)
 24H  17/1200Z 23.8N 126.1W   25 KT  30 MPH - Low (WSW San Carlos, Mexico)
 36H  18/0000Z 24.0N 127.1W   25 KT  30 MPH - Low (WSW San Carlos, Mexico)
 48H  18/1200Z 23.9N 128.2W   20 KT  25 MPH - Low (WSW San Carlos, Mexico)
 60H  19/0000Z 23.6N 129.5W   20 KT  25 MPH - Low (WSW San Carlos, Mexico)
 72H  19/1200Z...DISSIPATED

NWS Central Pacific Hurricane Center Honolulu HI 800 PM PDT Tue Sep 15, 2020

Satellite imagery shows that Karina’s outflow has improved over the past 6 hours, but persistent deep convection over the low-level center has shown some signs of warming/weakening in the last couple hours. The initial intensity for this advisory is maintained at 50 kt, primarily based on a blend of subjective Dvorak intensity estimates of 45-55 kt from SAB/TAFB/HFO.

Karina is moving toward the northwest at 10 kt (310/10 kt), steered by a mid- and upper-level ridge to the northeast and north, respectively. Although some relaxation of the recent northeasterly to easterly shear is expected to continue in the short-term, gradual weakening is expected as Karina is now over sub-26C water. As Karina rounds the southwestern portion of the deep-layer ridge in about 24 hours, south to southwesterly shear is expected to increase as the cyclone moves over even cooler waters and ingests increasingly dry air. This will lead to the demise of the cyclone, and Karina is expected to degenerate to a remnant low in a couple of days, dissipating shortly thereafter.

As the system weakens, it will be steered by the low-level northeasterly trade wind flow supplied by a surface high centered to the distant northwest, causing a slowing in forward speed, and a turn toward the west and southwest. The new official track forecast has changed little from the previous, and lies very close to the dynamical consensus TVCE. The new intensity forecast is little changed, and closely follows both the statistical and dynamical guidance.

FORECAST POSITIONS AND MAX WINDS

INIT  16/0300Z 21.3N 123.0W   50 KT  60 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 12H  16/1200Z 22.1N 124.2W   45 KT  50 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 24H  17/0000Z 23.0N 125.6W   40 KT  45 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 36H  17/1200Z 23.4N 126.7W   35 KT  40 MPH - Tropical Storm (WNW San Carlos, Mexico)
 48H  18/0000Z 23.5N 127.8W   30 KT  35 MPH - Depression (WNW San Carlos, Mexico)
 60H  18/1200Z 23.2N 129.0W   25 KT  30 MPH - Low (WNW San Carlos, Mexico)
 72H  19/0000Z 22.5N 130.2W   20 KT  25 MPH - Low (WNW San Carlos, Mexico)
 96H  20/0000Z...DISSIPATED

NWS Central Pacific Hurricane Center Honolulu HI 200 PM PDT Tue Sep 15, 2020

Latest satellite images show little significant change in the organization of deep convection associated with Karina since the previous advisory. Although the thunderstorms are primarily limited to the southwest semicircle, they remain over the center, and outflow in the northeast semicircle appears somewhat improved in the last couple of hours. A blend of subjective Dvorak current intensity estimates of 3.0/45 kt from SAB/HFO and 3.5/55 kt from TAFB supports maintaining an initial intensity of 50 kt.

Karina is crossing the 26C isotherm with an initial motion estimate of 305/10 kt, and much cooler waters lie along the forecast track. Karina is being steered by a mid- and upper-level ridge to the centered to the northeast and north respectively, and the short term forecast anticipates some relaxation of the recent northeasterly shear as Karina rounds the ridges. This should lead to slow weakening in the short term, and as south to southwesterly shear increases after about 24 hours, Karina will continue to weaken. Simulated satellite imagery based on HWRF guidance indicates the cyclone will become convection-free within about 48 hours, with dissipation following soon thereafter. As Karina weakens and becomes increasingly shallow, it will be steered by the low-level northeasterly trade wind flow supplied by a surface high centered to the distant northwest.

The updated track forecast lies along the same trajectory as the previous, but is shifted slightly southward due to recent observed motion, and is near the middle of guidance envelope. The intensity forecast is essentially unchanged and closely follows trends presented by SHIPS and FSSE.

FORECAST POSITIONS AND MAX WINDS

INIT  15/2100Z 20.7N 122.1W   50 KT  60 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 12H  16/0600Z 21.6N 123.3W   45 KT  50 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 24H  16/1800Z 22.5N 124.8W   40 KT  45 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 36H  17/0600Z 23.2N 126.0W   35 KT  40 MPH - Tropical Storm (WNW San Carlos, Mexico)
 48H  17/1800Z 23.5N 127.2W   30 KT  35 MPH - Depression (WNW San Carlos, Mexico)
 60H  18/0600Z 23.3N 128.4W   25 KT  30 MPH - Low (WNW San Carlos, Mexico)
 72H  18/1800Z 22.5N 129.5W   20 KT  25 MPH - Low (WNW San Carlos, Mexico)
 96H  19/1800Z...DISSIPATED

NWS National Hurricane Center Miami FL 800 AM PDT Tue Sep 15, 2020

Karina has changed little in organization over the past several hours with a concentrated area of deep convection mostly over the southwestern portion of the circulation and over the estimated position of the low-level center. The initial intensity is kept at 50 kt based on a blend of the latest Dvorak CI numbers from TAFB and SAB and the objective UW-CIMSS ADT.

Karina is now crossing the 26 isotherm, so it is unlikely that any further strengthening will occur. The cyclone is forecast to move over progressively cooler waters and into a drier, more stable atmosphere over the next couple of days. These conditions should induce a weakening trend soon, and the deep convection is expected to gradually wane during that time. Karina is forecast to become a convection-free remnant low by 60 h, or perhaps a little sooner. The latest NHC intensity forecast is in good agreement with the various guidance aids.

The initial motion of the tropical storm is 310/09 kt, as it continues to move along the periphery of a mid-level ridge to its northeast. This general motion should continue while the system maintains convection. As the system becomes devoid of convection, a turn to the west and west-southwest is anticipated as the cyclone moves within the low-level flow.

FORECAST POSITIONS AND MAX WINDS

INIT  15/1500Z 20.4N 121.1W   50 KT  60 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 12H  16/0000Z 21.3N 122.2W   45 KT  50 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 24H  16/1200Z 22.4N 123.9W   40 KT  45 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 36H  17/0000Z 23.3N 125.2W   35 KT  40 MPH - Tropical Storm (WNW Todos Santos, Mexico)
 48H  17/1200Z 23.7N 126.2W   30 KT  35 MPH - Depression (WNW San Carlos, Mexico)
 60H  18/0000Z 23.9N 127.3W   25 KT  30 MPH - Low (WNW San Carlos, Mexico)
 72H  18/1200Z 23.5N 128.3W   25 KT  30 MPH - Low (WNW San Carlos, Mexico)
 96H  19/1200Z 22.6N 130.7W   20 KT  25 MPH - Low (WNW San Carlos, Mexico)
120H  20/1200Z...DISSIPATED

NWS National Hurricane Center Miami FL 800 AM PDT Mon Sep 14, 2020

There has been little change to the appearance of Karina over the past several hours, with a large area of deep convection remaining displaced mostly to the southwest of the center due to moderate northeasterly shear. Because the general appearance of the cyclone is unchanged, the initial intensity remains 40 kt based on earlier ASCAT data.

The shear is expected to slowly relax over the next 24 h while the system remains over relatively warm waters, and some slight strengthening is possible during that time. After 24 h, Karina is forecast to cross the 26 degrees C SST isotherm and begin to enter a drier, more stable atmospheric environment. These factors should cause Karina to steadily weaken beginning by late Tuesday. By 72 h, the cyclone should be over water temperatures of less than 24C, and the system is expected to degenerate to a remnant low by 96 h, if not sooner. The low is then forecast to dissipate by day 5. The NHC intensity forecast is unchanged from the previous one, and is in good agreement with the various multi-model consensus aids.

Karina has resumed a northwestward movement, and the initial motion is 305/7 kt. A northwestward motion is expected to continue while the deep convection persists, as the cyclone is steered by a mid-level ridge to its north and northeast. Once the cyclone has weakened and lost most of its convection, it is expected to turn toward the west under the influence of the low-level flow. The track guidance has shifted northward at most time frames, and the latest NHC track forecast has been adjusted to the right as well, but is still to the south of most of the track guidance.

FORECAST POSITIONS AND MAX WINDS

INIT  14/1500Z 18.1N 118.5W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 12H  15/0000Z 18.8N 119.4W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 24H  15/1200Z 20.0N 120.9W   45 KT  50 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 36H  16/0000Z 21.2N 122.4W   40 KT  45 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 48H  16/1200Z 22.3N 123.8W   35 KT  40 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 60H  17/0000Z 23.2N 125.2W   30 KT  35 MPH - Depression (WSW Cabo San Lucas, Mexico)
 72H  17/1200Z 23.7N 126.2W   30 KT  35 MPH - Depression (WSW Cabo San Lucas, Mexico)
 96H  18/1200Z 23.7N 127.6W   25 KT  30 MPH - Low (WSW Cabo San Lucas, Mexico)
120H  19/1200Z...DISSIPATED

NWS National Hurricane Center Miami FL 800 PM PDT Sun Sep 13, 2020

Karina’s satellite presentation is not terribly impressive, with the deep convection sheared well south of what appears to be a somewhat elongated low-level center by 15 to 20 kt of northerly shear. The subjective Dvorak Final-T numbers have decreased a little in the last 6 hours, but overall a blend of the objective and subjective satellite estimates yields an intensity of 40 kt for this advisory.

Karina only has a limited window for strengthening, with SSTs forecast to cool to 26C along the forecast track within 36 hours. With the shear forecast to persist during until the waters cool and the atmosphere dries out, the intensity guidance has trended downward again this cycle, and so has the NHC prediction, which is close to or a little above HCCA and higher than the simple consensus aids. Karina should become a remnant low in about 4 days and is expected to dissipate by day 5.

The initial motion estimate is 285/11. Karina should be steered generally west-northwestward for the next several days, followed by a turn toward the west in the low-level flow by 96 hours. The new NHC track forecast is similar to the previous one and lies near the middle of the guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT  14/0300Z 18.2N 117.1W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 12H  14/1200Z 18.7N 118.1W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 24H  15/0000Z 19.4N 119.7W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 36H  15/1200Z 20.2N 121.0W   45 KT  50 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 48H  16/0000Z 21.0N 122.1W   40 KT  45 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 60H  16/1200Z 21.8N 123.3W   35 KT  40 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 72H  17/0000Z 22.3N 124.5W   30 KT  35 MPH - Depression (WSW Cabo San Lucas, Mexico)
 96H  18/0000Z 22.5N 126.5W   25 KT  30 MPH - Low (WSW Cabo San Lucas, Mexico)
120H  19/0000Z...DISSIPATED

NWS National Hurricane Center Miami FL 200 PM PDT Sun Sep 13, 2020

A midday ASCAT pass revealed that Karina still has an elongated circulation and is likely still attached to the ITCZ/monsoon trough. The center is also displaced to the northeast of the deepest convection due to ongoing moderate northeasterly shear. The ASCAT data confirmed that the storm currently has maximum winds of 40 k, with most of the tropical-storm-force winds located over the southern semicircle. With the shear not expected to decrease from its current magnitude, only modest strengthening is expected during the next 36 hours or so while Karina remains over waters warmer than 26 degrees Celsius. The peak intensity shown in the official forecast has been adjusted downward to 50 kt, which is now the highest intensity shown by any of the intensity models. Colder waters and a drier, more stable atmosphere should induce gradual weakening after day 2, with Karina likely to lose all of its deep convection and become a remnant low by day 4.

Karina turned a little bit to the left today but still has a west-northwestward heading (290/10 kt). A mid-level ridge located to the north should keep Karina on a west-northwestward trajectory with some reduction in forward speed through day 4. Once it weakens to a remnant low, Karina is expected to turn westward, steered by lower-level trade winds. There is some north-south divergence among the track models during Karina’s expected remnant low stage, but the overall guidance envelope has not shifted. Therefore, the updated NHC track forecast is not too different from the previous one and lies close to the HCCA, Florida State Superensemble, and TVCE multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT  13/2100Z 17.8N 116.0W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 12H  14/0600Z 18.5N 117.1W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 24H  14/1800Z 19.1N 118.6W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 36H  15/0600Z 19.8N 120.1W   50 KT  60 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 48H  15/1800Z 20.5N 121.3W   45 KT  50 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 60H  16/0600Z 21.2N 122.4W   40 KT  45 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 72H  16/1800Z 21.9N 123.6W   35 KT  40 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 96H  17/1800Z 22.5N 126.0W   30 KT  35 MPH - Low (WSW Cabo San Lucas, Mexico)
120H  18/1800Z 22.5N 128.5W   20 KT  25 MPH - Low (WSW Cabo San Lucas, Mexico)

NWS National Hurricane Center Miami FL 900 AM MDT Sun Sep 13, 2020

Karina’s center is a little bit closer to the deep convection this morning, resulting in intensity estimates increasing slightly. Based on Dvorak estimates of T3.0/45 kt and T2.5/35 kt from TAFB and SAB, respectively, and an overnight SATCON estimate of 42 kt, Karina’s initial intensity is assumed to be 40 kt. The moderate northeasterly shear currently affecting the cyclone is not expected to change appreciably during the next few days. However, Karina will remain over ocean waters warmer than 26 degrees Celsius for the next 48 hours, which should allow for a gradual intensification trend during that period. The shear is forecast to lighten up in 3-4 days, but by then Karina will be over colder waters and in a drier, more stable environment, which should induce weakening. Karina is likely to lose all of its deep convection and become a remnant low by the end of the forecast period. The NHC intensity forecast is generally close to the HCCA aid and the IVCN intensity consensus and shows weakening starting a little sooner than before.

Karina is moving toward the west-northwest (300/9 kt), south of a mid-level ridge axis which extends from northwestern Mexico southwestward over the Pacific. This ridge should keep Karina on this general heading with a very gradually decreasing forward speed through day 4. Once the cyclone weakens to a remnant low, it is expected to turn westward, steered by lower-level trade winds. No significant changes in the track forecast were required compared to the previous prediction, and the official forecast lies generally close to the multi-model consensus aids.

FORECAST POSITIONS AND MAX WINDS

INIT  13/1500Z 17.6N 114.7W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 12H  14/0000Z 18.3N 115.8W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 24H  14/1200Z 19.0N 117.4W   45 KT  50 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 36H  15/0000Z 19.7N 119.0W   50 KT  60 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 48H  15/1200Z 20.2N 120.4W   55 KT  65 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 60H  16/0000Z 20.9N 121.6W   50 KT  60 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 72H  16/1200Z 21.7N 122.8W   50 KT  60 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 96H  17/1200Z 22.6N 125.2W   35 KT  40 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
120H  18/1200Z 22.8N 127.7W   25 KT  30 MPH - Low (WSW Cabo San Lucas, Mexico)

NWS National Hurricane Center Miami FL 900 PM MDT Sat Sep 12, 2020

The last few visible satellite images indicated convection growing closer to the center of a low pressure area that NHC has been tracking for the past few days. Since the low was already well-defined this afternoon, the development of organized deep convection means that a tropical depression has formed. The initial wind speed is set to 30 kt, which is a blend of the TAFB/SAB fixes and earlier ASCAT data. The depression is embedded within a moderate easterly wind-shear environment, partially related to its position in the larger ITCZ/monsoon trough structure. Global model guidance is in reasonable agreement on the large-scale circulation becoming focused on the new tropical cyclone and a slight relaxation of the shear during the next couple of days. This change should lead to gradual intensification, and the new forecast is between the model consensus and the corrected-consensus aids. Beyond 2-3 days, decreasing SSTs and increasing dry air entrainment should promote weakening, and that is reflected below.

The initial motion estimate is an uncertain northwestward or 315/08 kt. A mid-level ridge is forecast to build westward, causing the cyclone to move west-northwestward for a few days after the weekend. A westward turn is forecast at long range due to the shallow cyclone feeling the low-level ridge. One big uncertainty with this forecast is how it interacts with the larger ITCZ/monsoon trough circulation, including the remnants of Invest 91E. For now, it is assumed that only a slight slow down occurs as the depression becomes the dominant circulation in the area, and the forecast is more consistent with the GFS- or UKMET-based guidance. However, a slower ECMWF-like solution is also possible, but is being given less weight at this time.

FORECAST POSITIONS AND MAX WINDS

INIT  13/0300Z 16.7N 112.9W   30 KT  35 MPH - Depression (WSW Manzanillo, Mexico)
 12H  13/1200Z 17.5N 113.8W   35 KT  40 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 24H  14/0000Z 18.3N 115.4W   40 KT  45 MPH - Tropical Storm (WSW Manzanillo, Mexico)
 36H  14/1200Z 18.9N 116.9W   45 KT  50 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 48H  15/0000Z 19.5N 118.5W   50 KT  60 MPH - Tropical Storm (WSW Puerto Vallarta, Mexico)
 60H  15/1200Z 20.0N 119.9W   55 KT  65 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 72H  16/0000Z 20.5N 121.0W   55 KT  65 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
 96H  17/0000Z 21.5N 123.5W   45 KT  50 MPH - Tropical Storm (WSW Cabo San Lucas, Mexico)
120H  18/0000Z 21.5N 126.0W   30 KT  35 MPH - Depression (WSW Cabo San Lucas, Mexico)

NWS National Hurricane Center Miami FL 500 AM PDT Sat Sep 12, 2020

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

  • 1. An area of low pressure located about 700 miles west-southwest of the southern tip of the Baja California peninsula is producing disorganized showers and thunderstorms. Some slight development of this system is possible during the next day or two before it interacts with, and is possibly absorbed by, a larger weather disturbance to its east-southeast. * Formation chance through 48 hours…low…20 percent. * Formation chance through 5 days…low…20 percent.
  • 2. Another area of low pressure is located several hundred miles southwest of the coast of southwestern Mexico. This system is producing a large area of disorganized showers and thunderstorms well to the west of the center of the low. Environmental conditions appear conducive for development, and a tropical depression is likely to form over the weekend or early next week while the system moves west-northwestward at 10 to 15 mph away from the coast of Mexico. * Formation chance through 48 hours…high..70 percent. * Formation chance through 5 days…high…80 percent.

NWS National Hurricane Center Miami FL 500 PM PDT Fri Sep 11, 2020

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

  • 1. An area of low pressure located a little more than 600 miles southwest of the southern tip of the Baja California is producing disorganized showers and thunderstorms. Some slight development of this system is possible during the next day or two before it interacts with, and is possibly absorbed by, a larger weather disturbance to its east-southeast. * Formation chance through 48 hours…low…20 percent. * Formation chance through 5 days…low…20 percent.
  • 2. Another area of low pressure is located several hundred miles south-southwest of the coast of southwestern Mexico. This system is producing a large area of disorganized showers and thunderstorms well to the west of the center of the the low. Environmental conditions appear conducive for development, and a tropical depression is likely to form over the weekend or early next week while the system moves west-northwestward at 10 to 15 mph away from the coast of Mexico. * Formation chance through 48 hours…high..70 percent. * Formation chance through 5 days…high...80 percent.

NWS National Hurricane Center Miami FL 1100 AM PDT Fri Sep 11, 2020

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

  • 1. Shower activity associated with a low-pressure area located about 500 miles southwest of the southern tip of the Baja California peninsula remains minimal. Some development of this system, however, is still possible during the next day or two before it interacts with, and possibly becomes absorbed by, a larger weather disturbance to its east-southeast. * Formation chance through 48 hours…low…20 percent. * Formation chance through 5 days…low…20 percent.
  • 2. A broad area of low pressure located several hundred miles south-southwest of the coast of southwestern Mexico continues to produce a large area of disorganized showers and thunderstorms. Environmental conditions appear conducive for development of this system, and a tropical depression is likely to form over the weekend or early next week while the system moves west-northwestward at 10 to 15 mph away from the coast of Mexico. * Formation chance through 48 hours…medium…60 percent. * Formation chance through 5 days…high…80 percent.

NWS National Hurricane Center Miami FL 500 PM PDT Thu Sep 10, 2020

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

  • 1. A low-pressure area located about 400 miles southwest of the southern tip of the Baja California peninsula is producing a compact area of showers and thunderstorms. Some development of this system is possible during the next few days before it interacts with, and possibly becomes absorbed by, a larger weather disturbance to its east. * Formation chance through 48 hours…low…20 percent. * Formation chance through 5 days…low…30 percent.
  • 2. A broad area of low pressure located a few hundred miles south-southwest of the coast of southwestern Mexico continues to produce a large area of disorganized showers and thunderstorms. Environmental conditions appear conducive for development of this system, and a tropical depression could form over the weekend or early next week while the system moves west-northwestward at 10 to 15 mph away from the coast of Mexico. * Formation chance through 48 hours…medium…40 percent. * Formation chance through 5 days…medium…60 percent.

NWS National Hurricane Center Miami FL 1100 AM PDT Thu Sep 10, 2020

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

  • 1. A low pressure area located about 400 miles southwest of the southern tip of the Baja California peninsula is producing a compact area of showers and thunderstorms. Some development of this system is possible during the next few days before it interacts with, and possibly becomes absorbed by, a larger weather disturbance to its east. * Formation chance through 48 hours…low…20 percent. * Formation chance through 5 days…low…30 percent.
  • 2. A broad area of low pressure located about 350 miles south-southwest of the coast of southwestern Mexico continues to produce a large area of disorganized showers and thunderstorms. Environmental conditions appear conducive for development of this system, and a tropical depression could form over the weekend or early next week while the system moves west-northwestward at 10 to 15 mph away from the coast of Mexico. * Formation chance through 48 hours…medium…40 percent. * Formation chance through 5 days…medium…60 percent.

If this system is named, it will become Tropical Storm Karina.

Article Resources:

Recent Tropical Cruise Weather: