Fixed mortgage rates have definitely been rising, and recent forecasts generally indicate they are not going to drop again anytime soon. So is now the time to lock in a low fixed rate, if you haven't already?

A lot depends on your personal circumstances, of course. But if the weather forecast called for rain, and you were definitely planning to go outside, you would probably carry an umbrella. You also would know there was a chance the forecast might be wrong, but usually a greater likelihood it would be right.

So, if you are set on getting a fixed-rate loan to buy a home, or could benefit from a refinance to lower your rate, odds are this is a good time to do so before rates move any higher. Indeed, as Moneyrates.com senior financial analyst Richard Barrington pointed out in a recent forecast, this may very well be the one last once-in-a-lifetime opportunity.

Mortgage rates are artificially low right now thanks to a Federal Reserve mortgage bond-buying spree that Fed officials have said will end when unemployment improves enough. But although the popular 30-year fixed rate has spent most of 18 months below 4 percent, Barrington warns: "You don't want to count on 3.5-percent mortgage rates ever returning. Rates are more likely to move higher rather than lower over the next six to 12 months."

In his research, Barrington wanted to see "what normal really looks like" once the Fed backs off. And what he found was that by mid-2014, the average rate for a 30-year fixed mortgage could be above 6 percent.

But any discourse on the current state of mortgage rates and what to do about them should start by putting them in their current context. Sure, 4 percent is more than 3 percent, and 5 percent is more than 4. But historically speaking, rates are still low.

That said, it is never a good idea to try to anticipate the ups and downs of mortgage rates. If you are ready to buy or refinance, lock in your rate now. Don't gamble, especially since your rate-lock may allow your rate to float back down if rates recede. 

If your speculator instincts take hold, the experts suggest running the numbers every time rates move by a quarter percent or more. In Freddie Mac's recent national survey of mortgage rates, the 30-year rate jumped by 0.5 percent in one week. But that increase was extraordinary.

Next, understand the true cost of rising rates. On a $250,000, 30-year loan, the difference between payments at 4.25 percent and 4.5 percent is a relatively small $37 a month ($1,230 vs. $1,267). Rather inconsequential when you are already spending that much money.

But there are other options. One, says Wendy Cutrufelli of the Bank of the West in San Francisco, is to increase your down payment. Perhaps a gift from a family member can help here, or maybe you could borrow from your retirement fund. Hiking your down payment means borrowing less, which could qualify you for a lower rate.

Also consider an adjustable rate mortgage. Even though ARM rates are lower -- and could move even lower in a rising rate environment -- Barrington and others warn against an adjustable rate unless you know for certain you can get out of it before the first reset period.

Toward that end, though, Cutrufelli points out that most major institutions offer hybrid ARMs with fixed-rate periods of five and seven years -- and sometimes even 10 years -- before the first adjustment, which should give most people plenty of time to worry about higher rates later.

ARM rates are currently 1.5 percent to 1.75 percent lower than 30-year rates, so it should be easier to qualify. But while most 7-1 and 10-1 ARMs are typically qualified at the initial rate, the Bank of the West executive points out that current Fannie Mae underwriting guidelines call for qualifying borrowers at the current rate plus 2 percentage points.

Another possibility is a 15-year fixed loan. These shorter-term loans are generally priced at 1 point below their 30-year cousins. But even at a lower rate, they are often more costly because they amortize -- pay down -- over a much shorter period. Still, they're something to look at.

Finally, consider an interest-only loan. It's a dangerous choice, to be sure, and one that may not be around much longer under current federal legislation. But it's certainly a less expensive one, at least at the outset.

A reverse mortgage works best as a line of credit that allows seniors to meet their immediate needs, such as home repairs, while preserving the remaining balance as a nest egg in case of emergencies.

But many seniors have used reverse mortgages as a lifeline to deal with more urgent financial needs, such as avoiding foreclosure and paying off other household debts. And that's gotten some of them into financial hot water -- a situation Uncle Sam is trying to rectify by tightening program guidelines.

The National Council on Aging (NCA) says one-third of its counseling clients have mortgage debt that exceeds 50 percent of the value of their home. Using a reverse mortgage to pay off the existing mortgage and other household debt leaves these borrowers with little equity to fall back on.

As a result, the Federal Housing Administration is experiencing "technical" defaults on reverse mortgages. These are cases in which borrowers can't afford to pay their property taxes and homeowner's insurance.

The losses on these defaults take money from the FHA mortgage insurance fund. So the FHA is moving to tighten its requirements for seniors who apply for an FHA-insured reverse mortgage, which the agency calls a Home Equity Conversion Mortgage.

FHA pioneered the reverse mortgage and introduced the HECM product 24 years ago. Now, for the first time, the agency wants to impose a financial assessment test on borrowers.

The test will determine if the borrowers have enough remaining cash flow to pay their living expenses after meeting their HECM obligation to pay taxes and insurance.

For borrowers who flunk the measure, the lender would be required to use a portion of the loan's proceeds to create an escrow account. The amount of the account is still under discussion within the agency, but under consideration is a set-aside of two to three years' worth of taxes and insurance payments.

But it's also possible that the FHA may decide that every HECM borrower, not just those who fail the test, will have to set aside an amount for taxes and insurance in case of an emergency.

Consumer and industry groups support efforts to shore up the HECM program, which is expected to experience increasing demand from the aging baby boomer generation. But there are some concerns the FHA may tighten too much. Consequently, consumer groups want to be sure there is some flexibility, particularly for low-income seniors.

NCA senior director Ramsey Alwin stressed that the set-aside should take into account the numerous public and private programs that provide property tax relief for seniors.

The nonprofit group that provides HECM counseling operates a website -- benefitscheckup.org -- that lists 160 property tax relief programs across the country. It also lists programs that help with Medicare premiums and co-pays and provide assistance with prescription drug and utility costs.

"The average reverse mortgage borrower can identify $5,500 worth of savings a year" from these assistance programs, Alwin said. "That will free up their limited income and could put them on a better financial footing when it comes to the financial assessment."

Many seniors ended up in technical default because they took out a Standard Fixed Rate HECM loan, which FHA has "temporarily" withdrawn from the market.

The standard fixed-rate product turned out to be risky because the borrower had to take out all the equity at one time in one lump sum. As it turned out, too many people didn't know how to handle such a large amount of cash.

Many also ended up in default because they were facing a financial crisis, such as a foreclosure, and had to act quickly.

Seniors should be looking at the reserve mortgage option "early and often," Alwin advised. And they should decide before a crisis when they want to use home equity to supplement their income.

The NCA has a support tool on its website that helps people think through the implications of a reverse mortgage and consider other options to free up cash.

Alwin also pointed out that FHA offers a line of credit option -- the HECM Saver -- that is more "consumer friendly" than the standard fixed-rate product.

The Saver has lower upfront costs, and because it is an adjustable-rate product, the proceeds of the reverse mortgage don't have to be dispersed all at once. So the borrower can tap into his line of credit only as his needs dictate.

The Saver reverse mortgage allows the borrower to "pay off immediate needs and maintain the nest egg for a rainy day," Alwin said.

Jeff Taylor, a reverse mortgage consultant and the founder of Wendover Consulting, noted that the HECM program primarily offered a line of credit when FHA first rolled it out in 1989.

Despite some aversion to ARM products on the part of consumers, Taylor expects demand will revert back to the line of credit product, the unused portion of which grows annually, much like a savings account.

"We are seeing financial planners across the country taking a second look at the HECM Saver ARM program as an option for many seniors to bridge the gap -- so they don't have to sell their stock portfolios or other investments," Taylor said.

Mortgage rates are on the rise, making it even more difficult to finance a house. But that doesn't mean the market will flounder before it has had a chance to really get going.

For one thing, loan volumes usually boom when interest rates start to rise. That's the period when all those would-be buyers and refinancers who have been sitting on the fence decide it's the proverbial "right time" to take the plunge. After all, prices are still down substantially from the market peak. While you may no longer be able to nail a rate of 4 percent or less, a loan at 4.5 percent is still better than one at 5 or 6.

Real estate and mortgages have never been totally predictable. While rising rates should choke off refinancings, there are always niche markets that are going to go the other way. And the government has extended its popular HARP refinancing program so there will be a market, though no one can guess how large, for refinancing --regardless of what interest rates do.

Another niche currently booming is housing bonds. According to Thomson Reuters stats in The Bond Buyer, a trade newspaper, housing bond volumes have doubled so far in 2013. Last year through May, $3.1 billion of these instruments had been issued through 101 offerings. This year through May, that number is $6.2 billion through 140 offerings.

In general, consumers can't invest directly in housing bonds, but low- to moderate-income buyers and first-timers can still benefit from them. Housing bond proceeds are used by state housing finance agencies to buy down interest rates on residential mortgages for qualified borrowers.

When rates got down as low as 3.5 percent, how much of a break could there be? In other words, how low can you go? In New Mexico and some other states, the answer is: as low as 1 percent.

Housing finance agencies (HFAs) always manage to offer healthy discounts, even in a low-rate environment. And now that rates are rising, these state agencies will have a little more wiggle room to offer even more options. The result should be increased demand for more housing bonds.

But even before rates have made a serious turn upward, housing bonds are receiving a bump from a new structure that copies probably the most successful mortgage bonds of all time: the mortgage-backed security. The structure is called a "passthrough," and it is for investors who buy these securities in a "secondary" mortgage market designed to pump more lending cash into the system.

A passthrough functions much the way it sounds: The bank or agency that collects the mortgage payment takes a cut for its trouble and then passes through the rest of the money to the investor.

Trillions of dollars of mortgage-backed securities have used this structure. But with housing bonds, the passthrough has a provision investors are going to like:

In the typical passthrough, when a mortgage that has been bundled into the security prepays -- say, for instance, you sell your house and move, paying off your original mortgage and getting another one somewhere in its stead -- the money returns to the housing agency, which reinvests it in more affordable housing. But with the new structure, the investor receives the money, not the HFA.

Last year, according to The Bond Buyer, Minnesota became the first state to use a housing bond passthrough. Illinois, Indiana and Florida have since followed.

The HFAs are important players in the rental market, too. They administer a key federal program called the Low Income Housing Tax Credit, a major boon to the construction of new, affordable multi-family units.

Here's how this program works: HFAs take applications from developers in their states and, through a complex points system, decide to fund projects with the highest scores. Packagers called syndicators sell the tax credits to investors. Any investor can buy tax credits, whether or not they have any real interest in housing, and many do because they receive a double benefit. Not only do they get a tax credit, they can buy the credits at a discount that varies depending on market conditions.

But the net effect is that the investor is buying an equity-stake in these lower-income rental projects, helping to make them possible. Often, their investment is not enough to fund the deal completely. But in most cases, financing packages are cobbled together using tax credit money, money from the Affordable Housing Program of the nearest of the 12 Federal Home Loan banks, the Department of Housing and Urban Development's HOME funds and other sources.

This is how affordable housing projects get stitched together like the quilts your grandmother used to make. And because these finance quilts are made through the hard work of dedicated people all over the country, many families get to stay warm in new or existing houses or apartments they are able to afford -- no matter if interest rates are going up or down.