Bertha Almost a Hurricane...But Staying at Sea

...Bertha Strengthens A Little More As It Moves Northward Away From
The Bahamas...

Summary Of 500 Am Edt...0900 Utc...Information
Location...26.1n 73.6w
About 220 Mi...350 Km E Of Great Abaco Island
Maximum Sustained Winds...70 Mph...110 Km/H
Present Movement...N Or 350 Degrees At 16 Mph...26 Km/H
Minimum Central Pressure...999 Mb...29.50 Inches

Watches And Warnings
There Are No Coastal Watches Or Warnings In Effect.

Discussion And 48-Hour Outlook
At 500 Am Edt...0900 Utc...The Center Of Tropical Storm Bertha Was Located Near Latitude 26.1 North...Longitude 73.6 West.

Bertha Is Moving Toward The North Near 16 Mph...26 Km/H...And This General Motion Is Expected To Continue Today...Followed By A Gradual Turn Toward The North-Northeast And Northeast During The Next 48 Hours.

On The Forecast Track...Bertha Will Continue To Move Away From The Bahamas Today And Pass About Midway Between The U.S. East Coast And Bermuda On Tuesday.

Reports From A Noaa Hurricane Hunter Aircraft Indicate That Maximum Sustained Winds Have Increased To Near 70 Mph...110 Km/H...With Higher Gusts.

Additional Strengthening Is Expected During The Next Day Or So...And Bertha Is Forecast To Become A Hurricane Later Today.

Slow Weakening Is Expected To Begin By Late Tuesday.

Tropical-Storm-Force Winds Extend Outward Up To 160 Miles...260 Km From The Center.

Data From The Noaa Aircraft Indicate That The Minimum Central Pressure Is 999 Mb...29.50 Inches.

Hazards Affecting Land

Next Advisory
Next Complete Advisory...1100 Am Edt.

Forecaster Stewart


Tropical Storm Bertha Discussion Number 14
Nws National Hurricane Center Miami Fl
500 Am Edt Mon Aug 04 2014

Convection Has Been Pulsing Near The Center, But The Overall Convective Cloud Pattern Of Bertha Has Changed Little Since The Previous Advisory Due To Moderate Northwesterly Wind Shear.

Earlier Air Force Reserve Reconnaissance Wind Data Around 0500 Utc Supported A 55-Kt Intensity, Especially Since The Pressure Had Decreased 3 Mb Down To 1004 Mb. However, A Noaa Research Aircraft Has Just Started Its Investigation Of The Cyclone, And Surface Wind Data Support Increasing The Intensity To 60 Kt Along With A Central Pressure Fall To About 999 Mb.

Bertha Is Now Moving Northward Or 350/14 Kt.

There Remains No Significant Change To The Previous Track Forecast Or Reasoning.

The Latest Nhc Model Guidance Remains Tightly Clustered And In Excellent Agreement On Bertha Continuing To Move Around The Western Periphery Of The Bermuda-Azores High Pressure Ridge For The Next 36 Hours Or So, Followed By A Northeastward Acceleration Into The Mid-Latitude Westerlies Ahead Of A Deep-Layer Trough And Frontal System Currently Approaching The U.S. East Coast.

The Official Forecast Track Is Just A Tad To The Left Of The Previous Advisory, And Is Close To The Consensus Model Tvca. The 72-, 96-, And 120-Hour Positions Are Based On A Blend Of Input From The Noaa Ocean Prediction Center.

On The Forecast Track, Bertha Is Expected To Pass About Midway Between The U.S. Coast And Bermuda On Tuesday.

The Northwesterly Vertical Wind Shear That Has Been Plaguing Bertha For The Past Few Days Is Now Decreasing And Is Gradually Backing Around To A Southwesterly Direction.

In Fact, The Global Models Indicate That Bertha Will Move Underneath A 200 Mb Ridge Axis In 18-24 Hours, At Which Time We Should See The Cyclone Reach Hurricane Status.

That Intensity Should Be Short-Lived Since The Shear Is Forecast To Increase To More Than 30 Kt By 48 Hours And Beyond, Which Should Induce At Least Steady Weakening.

The Intensity, However, Has Been Held Higher Than Normal Due To Bertha's Expected Transition To An Extratropical Cyclone With Possible Baroclinic Energy Keeping The System Fairly Strong.

Extratropical Transition Is Expected By 72 Hours, But It Could Occur Sooner Due To 50 Kt Or More Of Shear And Ssts Around 20c By That Time.

The Nhc Intensity Forecast Is Similar To The Previous Advisory, Remaining Above The Consensus Models Icon And Ivcn, And Is Close To A Blend Of The Ships And Lgem Intensity Models.

Forecast Positions And Max Winds

Init 04/0900z 26.1n 73.6w 60 Kt 70 Mph
12h 04/1800z 28.6n 73.7w 60 Kt 70 Mph
24h 05/0600z 31.9n 72.9w 65 Kt 75 Mph
36h 05/1800z 35.0n 70.8w 65 Kt 75 Mph
48h 06/0600z 37.7n 67.0w 60 Kt 70 Mph
72h 07/0600z 43.4n 57.3w 55 Kt 65 Mph...Post-Trop/Extratrop
96h 08/0600z 47.5n 47.5w 50 Kt 60 Mph...Post-Trop/Extratrop
120h 09/0600z 49.5n 37.5w 45 Kt 50 Mph...Post-Trop/Extratrop

Forecaster Stewart