MIDSEASON MADNESS : TIME-SLOT SHIFTS, NEW SHOWS NOW THE RULE AT NETWORK TV.

Byline: Keith Marder Daily News Television Writer

Call it a television evolution.

Cable competition has forced network TV into a ``mini-September'' mode beginning tonight. The lineup may foreshadow an eventual break into two distinct seasons - September to February, and March to May.

It's simple math. A season of TV is 36 weeks long, and most series are budgeted for 22 to 26 episodes.

``The networks can't be arrogant by simply slotting and repeating like viewers have nowhere else to go,'' said Kelly Kahl, vice president of scheduling at CBS. ``They not only have somewhere else to go, they will go.''

In an effort to keep viewers, the nets are launching 15 new shows between now and mid-April including such names as Arsenio Hall, Pauly Shore, Sharon Lawrence and featuring pedigree producers such as David Kelley (``Picket Fences,'' ``Chicago Hope'') and Dick Wolf (``Law & Order,'' ``New York Undercover'').

What's on tap

Best bets of the midseason are the two dramas from these producers: ABC's ``The Practice'' (Kelley), starring Dylan McDermott as the head of a small Boston law firm that takes on the big guys (ABC, 10 p.m. Tuesdays) and NBC's ``Feds'' (Wolf), an ensemble drama about federal prosecutors (CBS, 9 p.m. Wednesdays).

On the comedy end, the best of the lot is ``Fired Up,'' in which ``NYPD Blue's'' Sharon Lawrence shows that she has comedy chops. Lawrence plays a sharklike executive who gets downsized and has to go into business with her former assistant. NBC has nestled this show comfortably between ``Seinfeld'' and ``ER'' at 9:30 p.m. Thursdays.

Using already-popular stars is a strategy that's worked so far this year. Bill Cosby, Michael J. Fox, Ted Danson and Mary Steenburgen all rolled out new shows, all relatively successful.

``Pauly'' gets high marks for its pop-culture references, but it must carry a warning label that will keep some people away: ``Pauly'' does star Pauly Shore. He plays a rich kid from Brentwood whose father marries a young bombshell. She thinks Pauly's a freeloader. He thinks she's a gold digger.

Arsenio Hall, the one-time knee-slapping night-talk host, is back on television with a sitcom, ``Arsenio,'' on ABC. It's not awful, but it does suffer from almost every sitcom cliche in the book: newlyweds learning to deal with each other, a wacky and annoying live-in brother, problems at the workplace.

Aaron Spelling has come up with ``Pacific Palisades,'' which could have been named ``90210: The Next Generation.'' According to Spelling, these people will be young professionals, older than the ``90210'' kids and younger than the evil-doers of ``Melrose Place.'' Preview tapes are not yet available for the show, which will air sometime in April.

Night moves

To accommodate the onslaught of new shows, the television schedule as you know it will be revamped.

Some big shows will be taking midseason breathers. Taking six weeks off will be ``NYPD Blue'' beginning Tuesday, ``ER'' beginning March 6, and ``Murphy Brown'' beginning March 21. ``Party of Five'' is ending early, as scheduled, on April 2.

Several other high-profile shows will be moved to new nights, notably CBS' ``Everybody Loves Raymond,'' which moves to Mondays; ABC's ``Ellen,'' going to Tuesdays; and NBC's ``Law & Order,'' which moves to Thursdays.

Such midseason shuffles have proven to be very significant for some shows. Some of the major hits that have launched in the middle of the television year are ``All in the Family,'' ``Dragnet'' and ``3rd Rock From the Sun.''

There are also some new shows that are just plain junk.

If you want a bad sitcom, try the show about a brassy New York woman who talks her way into a position at a temp agency on CBS' ``Temporarily Yours,'' which is not the only aptly named show on the new schedule. There is also ``Vital Signs,'' which did not have a review tape ready until two days before air - usually a bad sign - and ``Crisis Center,'' high on the melodrama.

Familiar TV territory

Looking for a rip-off? ``Buffy the Vampire Slayer'' on the WB speaks directly to ``Sabrina the Teenage Witch.''And, there's more of the teacher-show genre that filled the fall schedule. UPN will unveil ``Social Studies'' next month. It needs some remedial time.

CBS may have missed with ``Temporarily Yours,'' but it did make two moves of fall shows that viewers should appreciate.

``EZ Streets,'' the show that was so well done it was too good for television, is back. The show, in which good and evil often work the same side of the buffet table, aired twice in the fall before being yanked. It's back in the same time slot it failed in, 10 p.m. Wednesday, but this time it will be up against ``Prince Street,'' another new drama, instead of an established show like ``Law and Order.''

It also has a better lead-in, ``Feds,'' instead of ``Public Morals,'' unequivocally the worst show of the fall season.

Another big move made by CBS is taking ``Everybody Loves Raymond'' out of Friday-night purgatory and place it after ``Cosby'' in the 8:30 p.m. Monday slot.

It may be the last chance for these two quality shows.

The end of `Murder'

But it's probably too late for ``Murder One,'' which is being taken off the regular ABC schedule and will be wrapped up as a six-hour miniseries later in the year. Two years of quality did not translate into a big audience.

All the schedule changes will annoy viewers, but some network programmers see them as a fact of life - even the rest periods for big shows.

``In the past, it would have been unthinkable,'' Kahl said of hiatuses for hits, ``but I think we all know that what we're forced to do in March and April is to run a lot of reruns, which ticks viewers off. Schedule changes tick them off, too, but it's the lesser of two evils.''

To repeat, or not to repeat

Jeff Bader, an ABC vice president in charge of scheduling, sees it differently. He said it would be better to air six repeats during an eight-week run of ``NYPD Blue'' than it is to move a popular show.

``In a perfect world, we would not do that,'' Bader said. ``But you have to introduce new shows, and Tuesday at 10 p.m. is our best slot to introduce a new drama.''

He noted that this is the first time in ``NYPD Blue's'' four seasons that it will finish the season with six original episodes.

William P. Croasdale, president of the National Broadcast Division of Western Media International, agreed that midseason can be a frustrating time for faithful viewers.

``Viewers are in the habit of looking for their favorite shows at their favorite times,'' Croasdale said. ``When you start bouncing times, viewers get so confused they don't know where to look. With this little device called a remote control, they may never come back to your network.''

Meet the new shows

Television's second season is upon us, meaning you will get to sample, get hooked on, or disregard several new shows, all of which are listed here and all of which start within a week unless otherwise noted:

ABC

``Vital Signs,'' Thursdays, 9 p.m.

``Spy Games,'' Mondays, 8 p.m.

``The Practice,'' Tuesdays, 10 p.m.

``Arsenio,'' Wednesdays, 9:30 p.m.

CBS

``Temporarily Yours,'' Wednesdays, 8:30 p.m.

``Feds,'' Wednesdays, 9 p.m.

Fox

``Pauly,'' Mondays, 9:30 p.m.

``Lawless,'' Fridays, 8 p.m. (debuts March 21).

``Pacific Palisades,'' Wednesdays, 9 p.m. (starts April 9)

NBC

``Crisis Center,'' Fridays, 10 p.m.

``Just Shoot Me,'' Wednesdays, 9:30 p.m. (preview is Tuesday night).

``Prince Street,'' Wednesdays, 10 p.m. (March 6, then switches to Wednesdays).

``Fired Up,'' Thursdays, 9:30 p.m. (April 10).

UPN

``Social Studies,'' Tuesdays, 8:30 p.m. (March 18).

THE WB

``Buffy the Vampire Slayer,'' Mondays, 9 p.m. (two-hour premiere, 8 p.m. March 10).

``In the Dark,'' (to be scheduled).

``Smart Guy,'' (to be scheduled).

CAPTION(S):

7 Photos, Box

Photo: (1--Cover--Color) Sharon Lawrence of `NYPD Blue' fame shows she has some comedy chops as well in her new TV show, `Fired Up.'

(2--Cover--Color) Arsenio Hall is back on TV, this time with a sitcom debuting midseason.

(3--Cover--Color) WARNING: The new show `Pauly' does star Pauly Shore.

(4) Debi Mazar's character is looking for the perfect job in New York City on ``Temporarily Yours,'' premiering 8:30 p.m. Wednesday on CBS.

(5) Follow the ups and downs of federal prosecutors and agents with ``Feds,'' 9 p.m. Wednesday on CBS.

(6) ``Spy Game,'' a high-tech action-adventure series with Allison Smith, left, and Linden Ashby, premieres 8 p.m. Monday on ABC.

(7) Dylan McDermott stars in ``The Practice,'' which premieres 10 p.m. Tuesday on ABC.

Box: Meet the new shows (See Text)