Here's the Downtown Partnership news release:

CONGESTION ALERT: Artscape, Otakon, and Lombard Street
In addition to the start of the Lombard Street repaving on Wednesday, July 15, two large events this weekend are expected to bring tens of thousands of visitors to Downtown.
Artscape begins Friday, July 17 through Sunday, July 19, and roads near Penn Station are already closed as organizers prepare for the event.  More closures are expected during this week as event set up progresses.  (See details below.)
Meanwhile, Otakon, a conference for colorfully-dressed fans of anime and comic books, will be at the Baltimore Convention Center this weekend.  
In addition to traffic modifications, there will be on-street parking restrictions associated with Artscape and the Lombard Street repaving.  Be sure to follow posted parking restrictions as they will be aggressively enforced.
This will be a fun weekend Downtown and we encourage everyone to take advantage of all the events.  Whenever possible, use public or alternative transportation to these events.  Transit options and schedules can be found at http://www.mtamaryland.com.
Lombard Street – Alternate Route Update
In yesterday’s email about Lombard Street, officials suggested exiting the JFX at Mount Royal Avenue as an alternate route into Downtown.  However, this is not possible because it’s closed for Artscape.  Instead, we suggest taking the JFX exits for St. Paul Street, Guilford Street, or Fayette Street.  Alternatively, another possibility is using Martin Luther King Jr. Boulevard northbound on the Westside to reach your destination.
For alternative routes, traffic cameras, and updated information, please visit http://www.getarounddowntown.com.
Street closures and traffic modifications and recommended detours for Artscape
The following streets are already closed or limited to traffic and will remain so until Tuesday, July 21:
• Dolphin Street from Mt. Royal Avenue to Howard Street
• Mt. Royal Avenue closed from North Avenue to Charles Street, curb lane closures both north and southbound
• Cathedral Street closed north of Preston Street to Mt. Royal Avenue
• Preston Street closed between Cathedral and Howard Streets
• Oliver Street closed between Maryland Avenue and Mt. Royal Avenue
The following streets will closed beginning tomorrow, Wednesday, July 15 beginning at 10 am through Monday, July 20 at 6 am:
• South side curb lane closed on Preston Street from Mace Street to Cathedral Street
• North side curb lane closed on Lanvale Street from Mt. Royal Avenue to Rutter Street
• The following streets will be closed on Thursday, July 16 from 10 am through Monday, July 20 at 6 am (impact begins on Charles Street):
• North Charles Street closed from Mt. Royal Avenue to Lafayette Avenue. (I-83 RAMP WILL CLOSE AT THIS TIME)
• North side of E. Mt. Royal Avenue closed from St. Paul Street to Charles Street (South side E. Mt Royal Avenue from Charles Street to St. Paul Street will remain open for detoured traffic)
• W. Lanvale Street closed from Maryland Avenue to Charles Street
• E. Lanvale Street closed from Charles Street to Lovegrove Street
The following modifications will go into effect Friday, July 17 at 9 am until Monday, July 20 at 6 am:
• Both sides of Maryland Avenue closed from North Avenue to Preston Street
• Southbound JFX ramp to Maryland Avenue will be closed
• South side of E. Lafayette Avenue closed from Charles Street to St. Paul Street
• W. Lafayette Avenue from Charles Street to Falls Road will be made two-way to allow access to City Yards and Potts & Callahan
• W. Preston Street closed from Maryland Avenue to Cathedral Street (Access will be granted to Meyerhoff Garage patrons only)
• Two-way traffic will be installed on Park Avenue (next to the Meyerhoff) from Cathedral Street to the Symphony Center garage to allow festival parking
• Both sides of W. Lanvale Street closed from Mt. Royal Avenue to Rutter Street
• Both sides of W .Lafayette Ave closed form Mt. Royal Avenue to Rutter Street
Special Penn Drive Traffic Chute:
• Once Charles Street closes a traffic chute will be created, using traffic cones, during non festival hours to allow vehicles from Penn Drive to gain access to the I- 83 ramp. The right turn onto N. Charles Street will still be prohibited during these times.
Special Traffic Patterns:
• Special one-way traffic patterns will be implemented along various roadways in the vicinity of the festival to provide local access for area residents throughout the event. Note that on Sunday, July 19 from 9 am until 12 noon, Maryland Avenue will be converted to two-way traffic from Preston Street to Mt. Royal Avenue for morning church services. Congregational members trying to access the church should follow St. Paul Street to Preston Street, then Maryland Avenue to the parking lot.
Drivers will be detoured as follows:
• Southbound Mt. Royal Avenue traffic will be detoured east on North Avenue, south on St. Paul Street and back to Mt. Royal Avenue.
• Westbound Preston Street traffic will be detoured south on Maryland Avenue, to west on Chase Street, to north on Howard Street and back to Preston and Dolphin Streets.
• Southbound Maryland Avenue traffic will be detoured east on Biddle Street, to north on Calvert Street, to west on North Avenue and back to Mt. Royal Avenue.
• Northbound Mt. Royal Avenue traffic will be detoured east on Biddle Street, to north on Calvert Street, to west on North Avenue and back to Mt. Royal Avenue.