Manhattanhenge returns to midtown on Wednesday evening, and this time Mother Nature is planning to cooperate.

As you may recall, 2012's first iteration of Manhattanhenge was rained out. However, the viewing tips we shared that day still hold, and the mostly sunny skies expected for Wednesday evening should make viewing the spectacle this time around a cinch. Since Manhattanhenge happens only twice a year, this will be the last chance to see the show until May 2013. Wednesday will feature a full view of the setting sun through the urban canyons of midtown, with Thursday's showing limited to about half the sun's disk. If you plan on taking photos, be sure to add the hashtag #WSJhenge to your photos so we can retweet the best ones.

The American Museum of Natural History (homebase of Manhattanhenge enthusiast Neil deGrasse Tyson) is planning a day of festivities to mark the occasion, complete with an astrophysics Q-and-A and live viewing from the museum's Upper West Side location. No word yet on whether Dr. Tyson will join the event to share his views on the regulation of unruly behavior.

For the rest of the week, temperatures will begin a slow warmup back toward the 90s. A big pattern shift should occur sometime Saturday evening when the humidity will return once again via a warm front, amping up the uncomfortableness and once again banishing the recent series of refreshingly cool nights. Last week's warmth and mugginess will have a chance to return from its exile in the southeastern states once that frontal passage occurs. It's too early to say whether this switch will mark the start of a new heat wave, but longer range forecasts have been hinting at just that scenario for the past several days.

Wednesday's Greater New York forecast roundup: